US20090203979A1 - Implantable sensor electrodes and electronic circuitry - Google Patents
Implantable sensor electrodes and electronic circuitry Download PDFInfo
- Publication number
- US20090203979A1 US20090203979A1 US12/419,188 US41918809A US2009203979A1 US 20090203979 A1 US20090203979 A1 US 20090203979A1 US 41918809 A US41918809 A US 41918809A US 2009203979 A1 US2009203979 A1 US 2009203979A1
- Authority
- US
- United States
- Prior art keywords
- electronic circuitry
- sensor system
- signals
- pulses
- electronic circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N1/00—Electrotherapy; Circuits therefor
- A61N1/02—Details
- A61N1/04—Electrodes
- A61N1/05—Electrodes for implantation or insertion into the body, e.g. heart electrode
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
- A61B5/25—Bioelectric electrodes therefor
- A61B5/279—Bioelectric electrodes therefor specially adapted for particular uses
- A61B5/28—Bioelectric electrodes therefor specially adapted for particular uses for electrocardiography [ECG]
- A61B5/283—Invasive
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/14—Measuring resistance by measuring current or voltage obtained from a reference source
Definitions
- Embodiments of the present invention claim priority from a U.S. Provisional Application entitled “Implantable Sensor Electrodes and Electronic Circuitry,” Ser. No. 60/335,652, filed Oct. 23, 2001, the contents of which are incorporated by reference herein.
- the present invention relates to the field of sensor electronics and, in particular, to implantable sensor electrodes and implantable electronic circuits for sensors.
- physiological parameter sensors are available that may be implanted in vivo and left in an in vivo environment for six months to a year and longer. Such extended lengths of time in an in vivo environment have taxed previously available electronic circuitry used in connection with the physiological parameter sensors.
- physiological parameter sensors that may be placed in a vascular environment or other environment that may subject a physiological parameter sensor to constant fluid environments has increased the burden on electrodes used in conjunction with a biomolecule that may be part of the physiological parameter sensor. Because multiple electrodes may be used in physiological parameter sensing applications, fluids such as, for example, blood, may create multiple conductive paths across electrodes that compromise the integrity of measurements being made with the electrodes. Electrode configuration and associated circuitry known up to this point have been ill-equipped to handle the demands of such an environment.
- a physiological parameter sensor may be implanted in vivo
- a power source such as, for example, a lithium battery
- Such short term sensors may have been designed, for example, for emergency use in surgical applications where the intent was to keep the sensor powered even in storage.
- a hospital could store the sensors, implant them during emergency surgery, and expect to get sensor readouts immediately.
- storing a sensor with an activated power source may deplete the power source to such an extent that using the sensor for long term in vivo implantation may be impractical and even unadvisable.
- Implantable, in vivo automated systems require not only extended term power requirements for powering an implanted power sensor, but also require increased power availability for the circuitry used to obtain and process sensor signals.
- Embodiments of the present invention relate to sensor electrodes and sensor electronics interfaced to the sensor electrodes.
- Embodiments of the present invention include an electronic circuit for sensing an output of a sensor including at least one electrode pair for sensing a parameter.
- the at least one electrode pair may have a first electrode and a second electrode, wherein the first electrode wraps around the second electrode.
- the electronic circuit may contain circuitry for processing the parameter.
- the parameter sensed by the electrode pair may be a physiological parameter such as, for example, glucose or oxygen.
- the first electrode may wrap around the second electrode in a U-shaped fashion or may surround three sides of the second electrode.
- the layout of the first electrode and a second electrode may be such that it minimizes cross coupling between the first electrode and the second electrode.
- the electronic circuit may include a reference electrode for setting a reference voltage for the at least one electrode pair.
- the reference voltage may be set to about 0.5 volts.
- the circuitry may include a line interface for interfacing with input/output lines; a rectifier in parallel with the line interface; a counter connected to the line interface; and a data converter connected to the counter and the at least one electrode pair.
- Control logic may be connected to the counter and the line interface.
- the control logic may include a state machine and a state decoder connected to the state machine.
- the control logic may include a microprocessor.
- the rectifier may transfer power from communication pulses to a capacitor.
- the capacitor may power the electronic circuit using power stored from the communication pulses.
- the data converter may be an analog-to-digital converter, a voltage-to-frequency converter, or a current-to-frequency converter. If the data converter is a current-to-frequency converter, an output of the current-to-frequency converter may be scaled using a prescaler before connecting to the counter.
- the prescaler may be a divide-by-16 prescaler.
- the circuitry may also include a temperature sensor for reading a temperature of an environment and a voltage reference for applying a voltage to a reference electrode.
- switched capacitor circuits may be used as resistors in the electronic circuit.
- FIG. 1 shows a general block diagram of an electronic circuit for sensing an output of a sensor according to an embodiment of the present invention.
- FIG. 2 shows an electronic configuration of the sensor electrodes according to an embodiment of the present invention.
- FIG. 3 shows a graph of current versus voltage for varying levels of oxygen according to an embodiment of the present invention.
- FIG. 4 shows a physical electrode layout to minimize the effect of cross coupling between counter electrodes and working electrodes according to an embodiment of the present invention.
- FIG. 5 shows a detailed block diagram of an electronic circuit according to an embodiment of the present invention.
- FIG. 6 shows a transmitted pulse waveform according to an embodiment of the present invention.
- FIG. 7 shows a substrate having a first side which contains an electrode configuration and a second side which contains electronic circuitry according to an embodiment of the present invention.
- FIG. 8 shows an electrode side of a sensor substrate used with the spacers according to an embodiment of the present invention.
- FIG. 1 shows a general block diagram of an electronic circuit for sensing an output of a sensor according to an embodiment of the present invention.
- At least one pair of sensor electrodes 10 may interface to a data converter 12 , the output of which may interface to a counter 14 .
- the counter 14 may be controlled by control logic 16 .
- the output of the counter 14 may connect to a line interface 18 .
- the line interface 18 may be connected to input and output lines 20 and may also connect to the control logic 16 .
- the input and output lines 20 may also be connected to a power rectifier 22 .
- the sensor electrodes 10 may be used in a variety of sensing applications and may be configured in a variety of ways.
- the sensor electrodes 10 may be used in physiological parameter sensing applications in which some type of biomolecule is used as a catalytic agent.
- the sensor electrodes 10 may be used in a glucose and oxygen sensor having a glucose oxidase enzyme catalyzing a reaction with the sensor electrodes 10 .
- the sensor electrodes 10 along with a biomolecule or some other catalytic agent, may be placed in a human body in a vascular or non-vascular environment.
- the sensor electrodes 10 and biomolecule may be placed in a vein and be subjected to a blood stream, or may be placed in a subcutaneous or peritoneal region of the human body.
- FIG. 2 shows an electronic configuration of the sensor electrodes 10 according to an embodiment of the present invention.
- An op amp 30 or other servo controlled device may connect to sensor electrodes 10 through a circuit/electrode interface 38 .
- the op amp 30 may attempt to maintain a positive voltage between a reference electrode 32 and a working electrode 34 by adjusting the voltage at a counter electrode 36 .
- the voltage applied at an input of the op amp 30 and thus set at the reference electrode 32 may be approximately 0.5 volts.
- Current may then flow from a counter electrode 36 to a working electrode 34 . Such current may be measured to ascertain the electrochemical reaction between the sensor electrodes 10 and the biomolecule of a sensor that has been placed in the vicinity of the sensor electrodes 10 and used as a catalyzing agent.
- current may flow from a counter electrode 36 to a working electrode 34 only if there is oxygen in the vicinity of the enzyme and the sensor electrodes 10 .
- the voltage set at the reference electrode 32 is maintained at about 0.5 volts
- the amount of current flowing from a counter electrode 36 to a working electrode 34 has a fairly linear relationship with unity slope to the amount of oxygen present in the area surrounding the enzyme and the electrodes.
- increased accuracy in determining an amount of oxygen in the blood may be achieved by maintaining the reference electrode 32 at about 0.5 volts and utilizing this region of the current-voltage curve for varying levels of blood oxygen.
- FIG. 3 A graph of current versus voltage for varying levels of oxygen may be seen in FIG. 3 .
- Different embodiments of the present invention may utilize different sensors having biomolecules other than a glucose oxidase enzyme and may, therefore, have voltages other than 0.5 volts set at the reference electrode.
- more than one working electrode 34 may be used. However, although current may normally flow out of the op amp 30 toward the counter electrode 36 and then toward a corresponding working electrode 34 , in some applications where more than one working electrode 34 is used, current from a counter electrode 36 may be coupled to an unintended working electrode 34 . This phenomenon may occur because some environments in which the sensor may be used may provide multiple conductive paths from a counter electrode 36 to any of a plurality of working electrodes 34 . For example, when a sensor having a glucose oxidase enzyme is used in glucose and oxygen sensing applications and is placed in a vascular environment, blood surrounding the sensor may create a conductive path from a counter electrode 36 to any of a plurality of working electrodes 34 .
- the sensor electrodes 10 may be configured to minimize the effect of cross coupling between counter electrodes 36 and working electrodes 34 .
- FIG. 4 shows a physical electrode layout to minimize the effect of cross coupling between counter electrodes and working electrodes according to an embodiment of the present invention.
- Each counter electrode 40 , 42 wraps around a working electrode 44 , 46 in a U-shaped fashion.
- a reference electrode 48 may be positioned between the counter electrodes 40 , 42 .
- cross coupling between a first counter electrode 40 and a second working electrode 46 and a second counter electrode 42 and a first working electrode 44 may be minimized.
- the first and second counter electrodes 40 , 42 may be electronically coupled such that the voltage or electric potential of the counter electrodes 40 , 42 is equivalent.
- Electroplating may be accomplished with any of a variety of electroplating materials that are common in the industry, such as, for example, platinum, silver, silver chloride and the like.
- the electronic circuit may contain plating circuitry that may be used for this purpose.
- the electronic circuit may contain a plating circuit that is utilized only during the manufacturing process to facilitate electroplating of the electrodes.
- the sensor electrodes 10 may interface to a data converter 12 .
- the data converter 12 may be any type of analog-to-digital converter suitable for converting an electronic parameter coming from the sensor electrodes 10 into a form suitable for use by the remainder of the electronic circuit.
- the data converter may convert current to digital data or voltage to digital data.
- the data converter may convert current to frequency.
- a current-to-frequency converter suitable for use in an embodiment of the present invention is disclosed in U.S. Pat. No. 5,917,346, Low Power Current-to-Frequency Converter Circuit For Use In Implantable Sensors, by John C. Gord, assigned to the Alfred E. Mann Foundation, which is incorporated herein by reference.
- the counter 14 may be any counter commonly used in the industry such as, for example, a ripple counter.
- the control logic 16 may be any control logic that facilitates accurate operation of the counter 14 .
- the counter and control logic may operate in a synchronous or asynchronous mode.
- the counter 14 and control logic 16 may be implemented in a variety of ways, such as, for example, with discrete devices or with a microprocessor.
- the line interface 18 may receive information in a variety of forms such as, for example, in pulses, from a remotely located implant unit or other device to which the electronic circuit is interfaced.
- the line interface 18 may generate data and clock signals for use by other parts of the electronic circuitry from such information.
- the line interface 18 may also send information in the form of pulses, for example, back to the implant unit or other device to which it is interfaced.
- the power rectifier 22 may take power from communication signals incident on the input lines 20 and store such power on a storage device such as, for example, a capacitor. According to embodiments of the present invention, there is no internal energy generating device such as, for example, a battery, resident in the electronic circuit. Power is derived from the communication signals using the power rectifier 22 . Thus, the electronic circuit may be used for long term sensing applications since there is no concern for depletion of an energy generating device such as, for example, a battery, within the electronic circuit.
- a power rectifier circuit suitable for use in an embodiment of the present invention is disclosed in U.S. Pat. No. 5,999,849, Low Power Rectifier Circuit For Implantable Medical Device, by John C. Gord et al, assigned to the Alfred E. Mann Foundation, which is incorporated herein by reference.
- FIG. 5 shows a more detailed block diagram of an electronic circuit according an embodiment of the present invention.
- Input/output lines 20 connect to a line interface 18 and power rectifier 22 and provide a communications link between the electronic circuit and a remotely located implant unit or other device.
- a remotely located implant unit or other device may communicate with the electronic circuit using a series of bipolar pulses transmitted across the input/output lines.
- a transmitted pulse waveform may be seen in FIG. 6 .
- Each bipolar pulse 50 , 52 , 54 , 56 may represent one bit of data from the remotely located implant unit or other device communicating with the electronic circuit.
- Each bipolar pulse 50 , 52 , 54 , 56 may comprise a positive and a negative level.
- a binary one may be designated by a positive level followed by a negative level.
- a positive level not followed by a negative level may designate a binary zero.
- transmit pulse amplitudes may be between 2.3 volts and 3.6 volts.
- a first pulse 50 transmitted is a positive pulse and is followed by a negative pulse.
- the pair of pulses 50 , 52 indicate a binary one according to an embodiment of the present invention.
- the second pair of pulses 54 , 56 in FIG. 6 is a negative pulse followed by a positive pulse.
- the second pair of pulses 54 , 56 represent a binary zero.
- a zero voltage level may exist between positive and negative pulses.
- a pulse width 58 may be approximately 1.9 micro seconds.
- the pulses may have a pulse repetition rate of 4,096 hertz, corresponding to a period 60 of approximately 244 microseconds.
- the electronic circuit may be implemented with a variety of communication delays built in so that the integrity of data transmissions may be increased.
- a 152 microsecond delay after receipt of a pair of transmitted pulses may be used for ignoring other pulses on the input/output lines.
- confusion as to the intended recipient of the pulses may be decreased if, for example, there are a plurality of electronic circuits using the same input/output lines or of the electronic circuit has put its own pulses onto the input/output lines.
- the electronic circuit may respond in a variety of ways depending on the opcode or data received. For example, the electronic circuit may respond by outputting a counter value, a trim setting value, a mode status, a channel setting, an identification number that has been permanently etched onto the circuit, or the like. According to an embodiment of the present invention, the electronic circuit may respond in the form of unipolar pulses. For example, if the response value is a binary one, the electronic circuit may set a logic high using a positive pulse for a duration from between one to ten microseconds, nominally 44 microseconds after the first edge of the bipolar pulse received from the remotely located implant unit or other device.
- the amplitude of the pulses sent by the electronic device to the remotely located implant unit or other device may be between one volt and 3.6 volts. If the response from the electronic circuit is a binary zero, no pulse may be sent by the electronic circuit to the remotely located implant unit or other device.
- the input lines 20 may be fed to a power rectifier 22 which uses pulses incident on the input lines 20 to charge a capacitor 19 .
- Electrical charge stored in the capacitor 19 extracted from the communication pulses on the input lines 20 may be used to power the electronic circuit.
- the capacitor 19 may also act as a low pass filter for the electronic circuit to reduce voltage ripple. According to an embodiment of the present invention, using a pulse width of 2 microseconds every 244 microseconds, the capacitance may be about 0.033 microfarads. Because a capacitor of this size may be too large for an integrated device, if the electronic circuit is fabricated as an integrated circuit, the capacitor 19 may be a discrete capacitor external to the electronic circuit. According to an embodiment of the present invention, the capacitor may be charged to +/ ⁇ 3 volts.
- the input lines 20 may also be connected to a line interface 18 which, according to an embodiment of the present invention, may receive information in a form such as, for example, bipolar pulses from a remotely located implant unit or other device.
- the line interface 18 may also generate data and clock signals and may also send unipolar pulses back to the remotely located implant unit or other device.
- a state machine 70 and state decoder 72 may be connected to the line interface 18 .
- Data and clock signals generated by the line interface 18 may be used by the state machine 70 to extract data and to determine the nature of the bipolar pulses received on the input lines 20 .
- the state machine 70 may provide a variety of functions for the electronic circuit. For example, the state machine 70 may generate system clocks, clear counters, check parity and the like.
- the state machine 70 may also decode opcodes and data. Decoded opcodes may designate a variety of functions such as, for example, latching a new multiplexer channel setting, setting trim values and setting a test mode.
- the state decoder 72 may be used to decode counter outputs.
- the state machine 70 and state decoder 72 may include a power-on clear circuit 74 .
- the power-on clear circuit 74 may be a typical RC type pulse generation circuit having a 50 picofarad capacitor, a transistor acting as a resistor, and two inverters to square a pulse.
- the state machine 70 and state decoder 72 may interface to an input latch 76 .
- the input latch 76 may be used to latch addresses, opcodes and data used in a command.
- the input latch 76 may feed a trim latch 78 , an address matching circuit 80 and a channel latch 82 .
- the channel latch 82 may comprise a plurality of latches with data inputs from the input latch 76 .
- the channel latch 82 may be used to control prescalers and multiplexers.
- the trim latch 78 may also consist of a plurality of latches. Inputs to the trim latch 78 may contain trim sitting data. Once latched, the trim sitting may be maintained until the next trim setting operation or until a power-on reset occurs.
- trim settings may have secret handshakes. Because trim settings may greatly affect the operation of the electronic circuit, care may be taken to minimize errors when setting trim voltages. For example, the electronic circuit may receive specific commands with no other commands in between before trim voltages are set.
- the address matching circuit 80 may be used to verify that instructions and data sent to an electronic circuit are being received by the intended electronic circuit. In applications where multiple sensors, sensor electrodes and sensor electronic circuits are used, the address matching circuit 80 can verify that each electronic circuit receives instructions and data intended for it. For example, in some applications, several electronic circuits may be daisy chained together. Because each electronic circuit may have a unique address, instructions and data sent over a serial bus may be received by each electronic circuit but intended for only one electronic circuit. The address matching circuit 80 will read the address for which the instructions and data are intended and compare that address to the address of the electronic circuit in which the address matching circuit 80 is resident. If the address read by the address matching circuit 80 matches the address of the electronic circuit, the instructions and data will be used by the electronic circuit. If the address read by the address matching circuit 80 does not match the address of the electronic circuit, the instructions and data will be ignored by the electronic circuit.
- the channel latch 82 may feed a channel decoder 84 .
- the channel decoder 84 may decode channel bytes from the channel latch 82 into channel select signals.
- the channel decoder 84 signals may then be used to control an analog multiplexer 86 for the selection of auxiliary signals for measurement.
- the analog multiplexer 86 may multiplex auxiliary signals to a data converter for measurement.
- the analog multiplexer 86 may be an eight channel CMOS multiplexer. If voltage signals are multiplexed out of the analog multiplexer, they may be directed to a switched capacitor resistor 88 for conversion of the voltages to currents, thereby putting the voltages in a form that may be measured by current to frequency converters.
- a discrete resistor or a transistor used as a resistor may be used in place of the switched capacitor resistor 88 , the switched capacitor resistor 88 is used because it is generally smaller than other types of resistors and takes up less space in the electronic circuit.
- a temperature sensor 90 may be fed into the analog multiplexer 86 providing an output current that is function of temperature.
- nominal output current from the temperature sensor 90 may be 50 nanoamps and may change by 1 nanoamp per degree Celsius.
- the temperature sensor 90 may be included in the electronic circuit to provide proper calibration of the electronic circuit. For example, a patient with a fever may cause a different glucose/oxygen reaction than a patient with a normal body temperature. The temperature sensor 90 may be used to compensate for this difference.
- current-to-frequency 92 , 94 , 96 converters may be used in the electronic circuit shown in FIG. 5 .
- Current-to-frequency converters 92 , 94 , 96 provide an easy method by which to count cycles, consume very low power, automatically average, and make current measurement relatively inexpensive.
- current-to-frequency converters 92 , 94 , 96 are conducive to measuring current through the working electrodes 34 while holding the working electrodes 34 at ground without using a negative power supply. Current passing from the counter electrodes 36 to the working electrodes 34 tends to drive the working electrodes 34 above ground.
- the current-to-frequency converters 92 , 94 , 96 emit negative charge packets.
- the working electrodes 34 may be maintained at ground. This is because the negative charge packets emitted by the current-to-frequency converters 92 , 94 , 96 tend to offset the current from the counter electrodes 36 tending to drive the working electrodes 34 above ground.
- the current-to-frequency 92 , 94 , 96 converters may be calibrated in a variety of ways. According to an embodiment of the present invention, the current-to-frequency 92 , 94 , 96 converters may calibrated at about 100 counts/sec/nanoamp. The calibration of the current-to-frequency 92 , 94 , 96 converters may depend on a variety of factors including, without limitation, the length of the counting time and any current-to-frequency conversion factors.
- the current-to-frequency converters 92 , 94 , 96 may feed prescalers 98 , 100 , 102 .
- the prescalers 98 , 100 , 102 may be used to modify the output of the current-to-frequency converters 92 , 94 , 96 .
- the prescalers 98 , 100 , 102 may simply be divide by 16 circuits that reduces the number of counts seen by the measurement counters 104 , 106 , 108 . In this way, the burden on the measurement counters 104 , 106 , 108 is minimized and risk of the measurement counters 104 , 106 , 108 overflowing is reduced.
- the electronic circuit may be designed such that use of the prescalers 98 , 100 , 102 is optional by setting a flag or other indicator.
- the measurement counters 104 , 106 , 108 may be used to measure the output of the current-to-frequency converters 92 , 94 , 96 or to measure auxiliary signals. By knowing the count of the frequency output by the current-to-frequency converters 92 , 94 , 96 , the length of the counting time, and any current-to-frequency conversion factors used by the current-to-frequency converters 92 , 94 , 96 , the current generated by the sensor may be calculated.
- the measurement counters 104 , 106 , 108 may contain their own multiplexers.
- the measurement counters 104 , 106 , 108 , or the multiplexers on the measurement counters 104 , 106 , 108 may feed a general output multiplexer 110 which sends count values to the line interface 18 .
- the line interface 18 may then send these count values back to a remotely located implant unit or other device.
- the electronic circuit may also contain a voltage reference 112 .
- the voltage reference 112 may take a variety of forms.
- the voltage reference 112 may be a band gap reference circuit and may provide bias voltages used to provide known currents to transistors.
- the electronic circuit may also contain a variety of other elements.
- the electronic circuit may contain a test pad used for test purposes.
- a clock may be fed into the test pad to exercise the counters.
- the test pad may also be configured as an output so that on-chip voltage references may be measured.
- the electronic circuit may also contain variable bias circuitry.
- variable bias circuitry In order for the electronic circuit to operate quickly, a significant amount of bias current may be required to drive the transistors included in the circuit. However, there may be extended periods of time when the electronic circuit engages in very little activity. During periods of little activity, the variable bias circuitry may decrease the amount of bias current available to the electronic circuit. In addition, as soon as the voltage on the input lines varies by a threshold amount such as, for example, a volt or so, the variable bias circuitry may increase the amount of bias current available to the electronic circuit so that all of the functions of the electronic circuit may operate quickly. Thus, the variable bias circuitry may provide a dynamically adjustable bias current for the electronic circuit. The variable bias circuitry may anticipate pulses being received on the input lines so that, when the pulses arrive at the electronic circuit, an adequate amount of bias current is available for fast operation of the electronic circuit.
- the electronic circuit may be implemented in a variety of ways.
- the electrodes and the circuitry may be affixed to a single substrate.
- FIG. 7 shows a substrate 120 having two sides, a first side 122 of which contains an electrode configuration and a second side 124 of which contains electronic circuitry.
- a first side 122 of the substrate comprises two counter electrode-working electrode pairs 40 , 42 , 44 , 46 on opposite sides of a reference electrode 48 .
- a second side 124 of the substrate comprises electronic circuitry.
- the electronic circuitry may be enclosed in a hermetically sealed casing 126 , providing a protective housing for the electronic circuitry.
- the sensor substrate 120 may be inserted into a vascular environment or other environment which may subject the electronic circuitry to fluids.
- the electronic circuitry may operate without risk of short circuiting by the surrounding fluids.
- pads 128 are also shown in FIG. 7 to which the input and output lines of the electronic circuitry may be connected.
- the electronic circuitry itself may be fabricated in a variety of ways. According to an embodiment of the present invention, the electronic circuitry may be fabricated as an integrated circuit using techniques common in the industry.
- FIG. 8 shows an electrode side of a sensor substrate 120 used with the spacers 130 according to an embodiment of the present invention.
- the embodiment shown in FIG. 8 may be used for physiological parameter sensing such as, for example, glucose sensing in the human body.
- the spacer 130 may be placed on top of the electrodes 40 , 42 , 44 , 46 , 48 . If the spacer 130 is made of silicon, for example, the spacer 130 may pass oxygen but will not pass glucose.
- a glucose oxidase enzyme may be placed in the indentation 132 of the spacer 130 , thereby resting over a second counter electrode-working electrode pair 42 , 46 .
- Oxygen passing through the silicon spacer 130 and reacting with a first counter electrode-working electrode pair 40 , 44 may be read by the current-to-frequency converters and used to establish a reference amount of oxygen in the blood.
- Glucose reacting with the glucose oxidase enzyme seated over the second counter electrode-working electrode pair 42 , 46 will tend to use up oxygen, leaving less oxygen available for reaction with the second counter electrode-working electrode pair 42 , 46 . Nonetheless, the remaining amount of oxygen will still react with the second counter electrode-working electrode pair 42 , 46 , and this value may be read by the current-to-frequency converter to which it is connected.
- the values out of each current-to-frequency to converter may be read and the differing amounts of oxygen may be used to determine the amount of glucose in the blood.
- the amount of glucose in the blood may be used to automatically deliver insulin to a patient using an implantable pump or other device.
Abstract
An electronic circuit for sensing an output of a sensor having at least one electrode pair and circuitry for obtaining and processing the sensor output. The electrode pair may be laid out such that one electrode is wrapped around the other electrode in a U-shaped fashion. The electronic circuitry may include, among other things, a line interface for interfacing with input/output lines, a rectifier in parallel with the line interface, a counter connected to the line interface and a data converter connected to the counter and the electrode pair. The data converter may be a current-to-frequency converter. In addition, the rectifier may derive power for the electronic circuit from communication pulses received on the input/output lines.
Description
- Embodiments of the present invention claim priority from a U.S. Provisional Application entitled “Implantable Sensor Electrodes and Electronic Circuitry,” Ser. No. 60/335,652, filed Oct. 23, 2001, the contents of which are incorporated by reference herein.
- 1. Field of the Invention
- The present invention relates to the field of sensor electronics and, in particular, to implantable sensor electrodes and implantable electronic circuits for sensors.
- 2. Description of Related Art
- The development of sensors that can survive for extended periods in less than ideal environments has increased the burden on associated electronics used to obtain and process signals received from such sensors. For example, in the medical device field, physiological parameter sensors are available that may be implanted in vivo and left in an in vivo environment for six months to a year and longer. Such extended lengths of time in an in vivo environment have taxed previously available electronic circuitry used in connection with the physiological parameter sensors.
- In addition, the availability of physiological parameter sensors that may be placed in a vascular environment or other environment that may subject a physiological parameter sensor to constant fluid environments has increased the burden on electrodes used in conjunction with a biomolecule that may be part of the physiological parameter sensor. Because multiple electrodes may be used in physiological parameter sensing applications, fluids such as, for example, blood, may create multiple conductive paths across electrodes that compromise the integrity of measurements being made with the electrodes. Electrode configuration and associated circuitry known up to this point have been ill-equipped to handle the demands of such an environment.
- Moreover, the extended periods of time in which a physiological parameter sensor may be implanted in vivo have placed extra demands on the power sources driving the sensor electrodes and sensor electronics. For example, previous sensor technology, which may have been designed for relatively short term in vivo implantation of a sensor, may have included a power source, such as, for example, a lithium battery, for in vivo implantation along with the sensor. Such short term sensors may have been designed, for example, for emergency use in surgical applications where the intent was to keep the sensor powered even in storage. Thus, a hospital could store the sensors, implant them during emergency surgery, and expect to get sensor readouts immediately. However, with the advent of sensors for long term in vivo implantation, storing a sensor with an activated power source may deplete the power source to such an extent that using the sensor for long term in vivo implantation may be impractical and even unadvisable.
- In addition, the demand for enhanced in vivo signal processing has put even greater demands on an already overburdened in vivo power source. Implantable, in vivo automated systems require not only extended term power requirements for powering an implanted power sensor, but also require increased power availability for the circuitry used to obtain and process sensor signals.
- Embodiments of the present invention relate to sensor electrodes and sensor electronics interfaced to the sensor electrodes.
- Embodiments of the present invention include an electronic circuit for sensing an output of a sensor including at least one electrode pair for sensing a parameter. The at least one electrode pair may have a first electrode and a second electrode, wherein the first electrode wraps around the second electrode. The electronic circuit may contain circuitry for processing the parameter. The parameter sensed by the electrode pair may be a physiological parameter such as, for example, glucose or oxygen.
- The first electrode may wrap around the second electrode in a U-shaped fashion or may surround three sides of the second electrode. The layout of the first electrode and a second electrode may be such that it minimizes cross coupling between the first electrode and the second electrode.
- The electronic circuit may include a reference electrode for setting a reference voltage for the at least one electrode pair. The reference voltage may be set to about 0.5 volts.
- In addition, the circuitry may include a line interface for interfacing with input/output lines; a rectifier in parallel with the line interface; a counter connected to the line interface; and a data converter connected to the counter and the at least one electrode pair. Control logic may be connected to the counter and the line interface. The control logic may include a state machine and a state decoder connected to the state machine. The control logic may include a microprocessor.
- In the electronic circuit, the rectifier may transfer power from communication pulses to a capacitor. The capacitor may power the electronic circuit using power stored from the communication pulses.
- The data converter may be an analog-to-digital converter, a voltage-to-frequency converter, or a current-to-frequency converter. If the data converter is a current-to-frequency converter, an output of the current-to-frequency converter may be scaled using a prescaler before connecting to the counter. The prescaler may be a divide-by-16 prescaler.
- The circuitry may also include a temperature sensor for reading a temperature of an environment and a voltage reference for applying a voltage to a reference electrode. In addition, switched capacitor circuits may be used as resistors in the electronic circuit.
- These and other objects, features, and advantages of embodiments of the invention will be apparent to those skilled in the art from the following detailed description of embodiments of the invention when read with the drawings and appended claims.
-
FIG. 1 shows a general block diagram of an electronic circuit for sensing an output of a sensor according to an embodiment of the present invention. -
FIG. 2 shows an electronic configuration of the sensor electrodes according to an embodiment of the present invention. -
FIG. 3 shows a graph of current versus voltage for varying levels of oxygen according to an embodiment of the present invention. -
FIG. 4 shows a physical electrode layout to minimize the effect of cross coupling between counter electrodes and working electrodes according to an embodiment of the present invention. -
FIG. 5 shows a detailed block diagram of an electronic circuit according to an embodiment of the present invention. -
FIG. 6 shows a transmitted pulse waveform according to an embodiment of the present invention. -
FIG. 7 shows a substrate having a first side which contains an electrode configuration and a second side which contains electronic circuitry according to an embodiment of the present invention. -
FIG. 8 shows an electrode side of a sensor substrate used with the spacers according to an embodiment of the present invention. - In the following description of preferred embodiments, reference is made to the accompanying drawings which form a part hereof, and in which are shown by way of illustration specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the preferred embodiments of the present invention.
-
FIG. 1 shows a general block diagram of an electronic circuit for sensing an output of a sensor according to an embodiment of the present invention. At least one pair ofsensor electrodes 10 may interface to adata converter 12, the output of which may interface to acounter 14. Thecounter 14 may be controlled bycontrol logic 16. The output of thecounter 14 may connect to aline interface 18. Theline interface 18 may be connected to input andoutput lines 20 and may also connect to thecontrol logic 16. The input andoutput lines 20 may also be connected to apower rectifier 22. - The
sensor electrodes 10 may be used in a variety of sensing applications and may be configured in a variety of ways. For example, thesensor electrodes 10 may be used in physiological parameter sensing applications in which some type of biomolecule is used as a catalytic agent. For example, thesensor electrodes 10 may be used in a glucose and oxygen sensor having a glucose oxidase enzyme catalyzing a reaction with thesensor electrodes 10. Thesensor electrodes 10, along with a biomolecule or some other catalytic agent, may be placed in a human body in a vascular or non-vascular environment. For example, thesensor electrodes 10 and biomolecule may be placed in a vein and be subjected to a blood stream, or may be placed in a subcutaneous or peritoneal region of the human body. -
FIG. 2 shows an electronic configuration of thesensor electrodes 10 according to an embodiment of the present invention. Anop amp 30 or other servo controlled device may connect tosensor electrodes 10 through a circuit/electrode interface 38. Theop amp 30 may attempt to maintain a positive voltage between areference electrode 32 and a workingelectrode 34 by adjusting the voltage at acounter electrode 36. According to an embodiment of the present invention, the voltage applied at an input of theop amp 30 and thus set at thereference electrode 32 may be approximately 0.5 volts. Current may then flow from acounter electrode 36 to a workingelectrode 34. Such current may be measured to ascertain the electrochemical reaction between thesensor electrodes 10 and the biomolecule of a sensor that has been placed in the vicinity of thesensor electrodes 10 and used as a catalyzing agent. - In an embodiment of the present invention where a glucose oxidase enzyme is used as a catalytic agent in a sensor, current may flow from a
counter electrode 36 to a workingelectrode 34 only if there is oxygen in the vicinity of the enzyme and thesensor electrodes 10. If the voltage set at thereference electrode 32 is maintained at about 0.5 volts, the amount of current flowing from acounter electrode 36 to a workingelectrode 34 has a fairly linear relationship with unity slope to the amount of oxygen present in the area surrounding the enzyme and the electrodes. Thus, increased accuracy in determining an amount of oxygen in the blood may be achieved by maintaining thereference electrode 32 at about 0.5 volts and utilizing this region of the current-voltage curve for varying levels of blood oxygen. A graph of current versus voltage for varying levels of oxygen may be seen inFIG. 3 . Different embodiments of the present invention may utilize different sensors having biomolecules other than a glucose oxidase enzyme and may, therefore, have voltages other than 0.5 volts set at the reference electrode. - According to an embodiment of the present invention, more than one working
electrode 34 may be used. However, although current may normally flow out of theop amp 30 toward thecounter electrode 36 and then toward a corresponding workingelectrode 34, in some applications where more than one workingelectrode 34 is used, current from acounter electrode 36 may be coupled to an unintended workingelectrode 34. This phenomenon may occur because some environments in which the sensor may be used may provide multiple conductive paths from acounter electrode 36 to any of a plurality of workingelectrodes 34. For example, when a sensor having a glucose oxidase enzyme is used in glucose and oxygen sensing applications and is placed in a vascular environment, blood surrounding the sensor may create a conductive path from acounter electrode 36 to any of a plurality of workingelectrodes 34. Current passing through any electrode may generate oxygen at that electrode via electrochemical reaction. Thus, current passing from acounter electrode 36 to an unintended workingelectrode 34 may generate oxygen at that workingelectrode 34 and, consequently, give the impression that the oxygen at that workingelectrode 34 is the result of a reaction between oxygen in the blood and the glucose oxidase enzyme, ultimately resulting in false glucose readings. Such false readings could prove detrimental to a patient relying on such readings for an accurate, automatic injection of insulin into the bloodstream. Accordingly, thesensor electrodes 10 may be configured to minimize the effect of cross coupling betweencounter electrodes 36 and workingelectrodes 34. -
FIG. 4 shows a physical electrode layout to minimize the effect of cross coupling between counter electrodes and working electrodes according to an embodiment of the present invention. InFIG. 4 , there are twocounter electrodes electrode counter electrode electrode reference electrode 48 may be positioned between thecounter electrodes first counter electrode 40 and a second workingelectrode 46 and asecond counter electrode 42 and a first workingelectrode 44 may be minimized. The first andsecond counter electrodes counter electrodes - In addition, all the sensor electrodes may be electroplated. Electroplating may be accomplished with any of a variety of electroplating materials that are common in the industry, such as, for example, platinum, silver, silver chloride and the like. The electronic circuit may contain plating circuitry that may be used for this purpose. For example, the electronic circuit may contain a plating circuit that is utilized only during the manufacturing process to facilitate electroplating of the electrodes.
- Returning to
FIG. 1 , thesensor electrodes 10 may interface to adata converter 12. Thedata converter 12 may be any type of analog-to-digital converter suitable for converting an electronic parameter coming from thesensor electrodes 10 into a form suitable for use by the remainder of the electronic circuit. For example, the data converter may convert current to digital data or voltage to digital data. According to an embodiment of the present invention, the data converter may convert current to frequency. A current-to-frequency converter suitable for use in an embodiment of the present invention is disclosed in U.S. Pat. No. 5,917,346, Low Power Current-to-Frequency Converter Circuit For Use In Implantable Sensors, by John C. Gord, assigned to the Alfred E. Mann Foundation, which is incorporated herein by reference. - The
counter 14 may be any counter commonly used in the industry such as, for example, a ripple counter. Thecontrol logic 16 may be any control logic that facilitates accurate operation of thecounter 14. The counter and control logic may operate in a synchronous or asynchronous mode. Thecounter 14 andcontrol logic 16 may be implemented in a variety of ways, such as, for example, with discrete devices or with a microprocessor. - The
line interface 18 may receive information in a variety of forms such as, for example, in pulses, from a remotely located implant unit or other device to which the electronic circuit is interfaced. Theline interface 18 may generate data and clock signals for use by other parts of the electronic circuitry from such information. Theline interface 18 may also send information in the form of pulses, for example, back to the implant unit or other device to which it is interfaced. - The
power rectifier 22 may take power from communication signals incident on the input lines 20 and store such power on a storage device such as, for example, a capacitor. According to embodiments of the present invention, there is no internal energy generating device such as, for example, a battery, resident in the electronic circuit. Power is derived from the communication signals using thepower rectifier 22. Thus, the electronic circuit may be used for long term sensing applications since there is no concern for depletion of an energy generating device such as, for example, a battery, within the electronic circuit. A power rectifier circuit suitable for use in an embodiment of the present invention is disclosed in U.S. Pat. No. 5,999,849, Low Power Rectifier Circuit For Implantable Medical Device, by John C. Gord et al, assigned to the Alfred E. Mann Foundation, which is incorporated herein by reference. -
FIG. 5 shows a more detailed block diagram of an electronic circuit according an embodiment of the present invention. Input/output lines 20 connect to aline interface 18 andpower rectifier 22 and provide a communications link between the electronic circuit and a remotely located implant unit or other device. - According to an embodiment of the present invention, a remotely located implant unit or other device may communicate with the electronic circuit using a series of bipolar pulses transmitted across the input/output lines. A transmitted pulse waveform may be seen in
FIG. 6 . Eachbipolar pulse bipolar pulse FIG. 6 , afirst pulse 50 transmitted is a positive pulse and is followed by a negative pulse. Thus, the pair ofpulses pulses FIG. 6 is a negative pulse followed by a positive pulse. Thus, according to an embodiment of the present invention, the second pair ofpulses pulse width 58 may be approximately 1.9 micro seconds. The pulses may have a pulse repetition rate of 4,096 hertz, corresponding to aperiod 60 of approximately 244 microseconds. The pulse repetition rate may be adjustable according to the equation 4,096 Hertz/n, where n=1, 2, 3, 4, 5, 6, 7 or 8. - According to an embodiment of the present invention, the electronic circuit may be implemented with a variety of communication delays built in so that the integrity of data transmissions may be increased. For example, according to an embodiment of the present invention, a 152 microsecond delay after receipt of a pair of transmitted pulses may be used for ignoring other pulses on the input/output lines. By implementing such a delay, confusion as to the intended recipient of the pulses may be decreased if, for example, there are a plurality of electronic circuits using the same input/output lines or of the electronic circuit has put its own pulses onto the input/output lines.
- Following receipt of data bits by the electronic circuit from the remotely located implant unit or other device, the electronic circuit may respond in a variety of ways depending on the opcode or data received. For example, the electronic circuit may respond by outputting a counter value, a trim setting value, a mode status, a channel setting, an identification number that has been permanently etched onto the circuit, or the like. According to an embodiment of the present invention, the electronic circuit may respond in the form of unipolar pulses. For example, if the response value is a binary one, the electronic circuit may set a logic high using a positive pulse for a duration from between one to ten microseconds, nominally 44 microseconds after the first edge of the bipolar pulse received from the remotely located implant unit or other device. The amplitude of the pulses sent by the electronic device to the remotely located implant unit or other device may be between one volt and 3.6 volts. If the response from the electronic circuit is a binary zero, no pulse may be sent by the electronic circuit to the remotely located implant unit or other device.
- Returning to
FIG. 5 , the input lines 20 may be fed to apower rectifier 22 which uses pulses incident on the input lines 20 to charge acapacitor 19. Electrical charge stored in thecapacitor 19 extracted from the communication pulses on the input lines 20 may be used to power the electronic circuit. Thecapacitor 19 may also act as a low pass filter for the electronic circuit to reduce voltage ripple. According to an embodiment of the present invention, using a pulse width of 2 microseconds every 244 microseconds, the capacitance may be about 0.033 microfarads. Because a capacitor of this size may be too large for an integrated device, if the electronic circuit is fabricated as an integrated circuit, thecapacitor 19 may be a discrete capacitor external to the electronic circuit. According to an embodiment of the present invention, the capacitor may be charged to +/−3 volts. - The input lines 20 may also be connected to a
line interface 18 which, according to an embodiment of the present invention, may receive information in a form such as, for example, bipolar pulses from a remotely located implant unit or other device. Theline interface 18 may also generate data and clock signals and may also send unipolar pulses back to the remotely located implant unit or other device. - A
state machine 70 andstate decoder 72 may be connected to theline interface 18. Data and clock signals generated by theline interface 18 may be used by thestate machine 70 to extract data and to determine the nature of the bipolar pulses received on the input lines 20. Thestate machine 70 may provide a variety of functions for the electronic circuit. For example, thestate machine 70 may generate system clocks, clear counters, check parity and the like. Thestate machine 70 may also decode opcodes and data. Decoded opcodes may designate a variety of functions such as, for example, latching a new multiplexer channel setting, setting trim values and setting a test mode. Thestate decoder 72 may be used to decode counter outputs. In addition, thestate machine 70 andstate decoder 72 may include a power-onclear circuit 74. According to an embodiment of the present invention, the power-onclear circuit 74 may be a typical RC type pulse generation circuit having a 50 picofarad capacitor, a transistor acting as a resistor, and two inverters to square a pulse. - The
state machine 70 andstate decoder 72 may interface to aninput latch 76. According to an embodiment of the present invention, theinput latch 76 may be used to latch addresses, opcodes and data used in a command. - The
input latch 76 may feed atrim latch 78, anaddress matching circuit 80 and achannel latch 82. Thechannel latch 82 may comprise a plurality of latches with data inputs from theinput latch 76. Thechannel latch 82 may be used to control prescalers and multiplexers. Thetrim latch 78 may also consist of a plurality of latches. Inputs to thetrim latch 78 may contain trim sitting data. Once latched, the trim sitting may be maintained until the next trim setting operation or until a power-on reset occurs. - According to an embodiment of the present invention, trim settings may have secret handshakes. Because trim settings may greatly affect the operation of the electronic circuit, care may be taken to minimize errors when setting trim voltages. For example, the electronic circuit may receive specific commands with no other commands in between before trim voltages are set.
- The
address matching circuit 80 may be used to verify that instructions and data sent to an electronic circuit are being received by the intended electronic circuit. In applications where multiple sensors, sensor electrodes and sensor electronic circuits are used, theaddress matching circuit 80 can verify that each electronic circuit receives instructions and data intended for it. For example, in some applications, several electronic circuits may be daisy chained together. Because each electronic circuit may have a unique address, instructions and data sent over a serial bus may be received by each electronic circuit but intended for only one electronic circuit. Theaddress matching circuit 80 will read the address for which the instructions and data are intended and compare that address to the address of the electronic circuit in which theaddress matching circuit 80 is resident. If the address read by theaddress matching circuit 80 matches the address of the electronic circuit, the instructions and data will be used by the electronic circuit. If the address read by theaddress matching circuit 80 does not match the address of the electronic circuit, the instructions and data will be ignored by the electronic circuit. - The
channel latch 82 may feed achannel decoder 84. Thechannel decoder 84 may decode channel bytes from thechannel latch 82 into channel select signals. Thechannel decoder 84 signals may then be used to control ananalog multiplexer 86 for the selection of auxiliary signals for measurement. Theanalog multiplexer 86 may multiplex auxiliary signals to a data converter for measurement. Theanalog multiplexer 86, according to an embodiment of the present invention, may be an eight channel CMOS multiplexer. If voltage signals are multiplexed out of the analog multiplexer, they may be directed to a switchedcapacitor resistor 88 for conversion of the voltages to currents, thereby putting the voltages in a form that may be measured by current to frequency converters. Although a discrete resistor or a transistor used as a resistor may be used in place of the switchedcapacitor resistor 88, the switchedcapacitor resistor 88 is used because it is generally smaller than other types of resistors and takes up less space in the electronic circuit. - A
temperature sensor 90 may be fed into theanalog multiplexer 86 providing an output current that is function of temperature. According to an embodiment of the present invention, nominal output current from thetemperature sensor 90 may be 50 nanoamps and may change by 1 nanoamp per degree Celsius. Because some physiological parameter sensing applications are temperature dependent, such as, for example, a glucose oxygen reaction, precise calibration of the electronic circuitry depends on the temperature of the environment in which the electronic circuit is located, such as, for example, the human body. Therefore, thetemperature sensor 90 may be included in the electronic circuit to provide proper calibration of the electronic circuit. For example, a patient with a fever may cause a different glucose/oxygen reaction than a patient with a normal body temperature. Thetemperature sensor 90 may be used to compensate for this difference. - Several current-to-
frequency FIG. 5 . Current-to-frequency converters frequency converters electrodes 34 while holding the workingelectrodes 34 at ground without using a negative power supply. Current passing from thecounter electrodes 36 to the workingelectrodes 34 tends to drive the workingelectrodes 34 above ground. The current-to-frequency converters electrodes 34 to the current-to-frequency converters electrodes 34 may be maintained at ground. This is because the negative charge packets emitted by the current-to-frequency converters counter electrodes 36 tending to drive the workingelectrodes 34 above ground. - The current-to-
frequency frequency frequency - The current-to-
frequency converters prescalers prescalers frequency converters prescalers prescalers - The measurement counters 104, 106, 108 may be used to measure the output of the current-to-
frequency converters frequency converters frequency converters general output multiplexer 110 which sends count values to theline interface 18. Theline interface 18 may then send these count values back to a remotely located implant unit or other device. - The electronic circuit may also contain a
voltage reference 112. Thevoltage reference 112 may take a variety of forms. For example, thevoltage reference 112 may be a band gap reference circuit and may provide bias voltages used to provide known currents to transistors. - The electronic circuit may also contain a variety of other elements. For example, the electronic circuit may contain a test pad used for test purposes. A clock may be fed into the test pad to exercise the counters. The test pad may also be configured as an output so that on-chip voltage references may be measured.
- The electronic circuit may also contain variable bias circuitry. In order for the electronic circuit to operate quickly, a significant amount of bias current may be required to drive the transistors included in the circuit. However, there may be extended periods of time when the electronic circuit engages in very little activity. During periods of little activity, the variable bias circuitry may decrease the amount of bias current available to the electronic circuit. In addition, as soon as the voltage on the input lines varies by a threshold amount such as, for example, a volt or so, the variable bias circuitry may increase the amount of bias current available to the electronic circuit so that all of the functions of the electronic circuit may operate quickly. Thus, the variable bias circuitry may provide a dynamically adjustable bias current for the electronic circuit. The variable bias circuitry may anticipate pulses being received on the input lines so that, when the pulses arrive at the electronic circuit, an adequate amount of bias current is available for fast operation of the electronic circuit.
- The electronic circuit may be implemented in a variety of ways. According to an embodiment of the present invention, the electrodes and the circuitry may be affixed to a single substrate.
FIG. 7 shows asubstrate 120 having two sides, afirst side 122 of which contains an electrode configuration and asecond side 124 of which contains electronic circuitry. As may be seen inFIG. 7 , afirst side 122 of the substrate comprises two counter electrode-working electrode pairs 40, 42, 44, 46 on opposite sides of areference electrode 48. Asecond side 124 of the substrate comprises electronic circuitry. As shown, the electronic circuitry may be enclosed in a hermetically sealedcasing 126, providing a protective housing for the electronic circuitry. This allows thesensor substrate 120 to be inserted into a vascular environment or other environment which may subject the electronic circuitry to fluids. By sealing the electronic circuitry in a hermetically sealedcasing 126, the electronic circuitry may operate without risk of short circuiting by the surrounding fluids. Also shown inFIG. 7 arepads 128 to which the input and output lines of the electronic circuitry may be connected. - The electronic circuitry itself may be fabricated in a variety of ways. According to an embodiment of the present invention, the electronic circuitry may be fabricated as an integrated circuit using techniques common in the industry.
-
FIG. 8 shows an electrode side of asensor substrate 120 used with thespacers 130 according to an embodiment of the present invention. The embodiment shown inFIG. 8 may be used for physiological parameter sensing such as, for example, glucose sensing in the human body. Thespacer 130 may be placed on top of theelectrodes spacer 130 is made of silicon, for example, thespacer 130 may pass oxygen but will not pass glucose. A glucose oxidase enzyme may be placed in theindentation 132 of thespacer 130, thereby resting over a second counter electrode-workingelectrode pair silicon spacer 130 and reacting with a first counter electrode-workingelectrode pair electrode pair electrode pair electrode pair - While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that the invention is not limited to the particular embodiments shown and described and that changes and modifications may be made without departing from the spirit and scope of the appended claims.
Claims (21)
1.-22. (canceled)
23. A sensor system comprising:
one or more sensors configured to sense one or more parameters and to provide one or more signals corresponding to the one or more parameters; and
electronic circuitry configured to be coupled to a device and configured to:
receive the one or more signals from the one or more sensors; and
receive one or more information signals from the device;
wherein the electronic circuitry is configured for implantation in a living body, and
wherein, upon the implantation of the electronic circuitry in the living body, the electronic circuitry is located external of the device.
24. The sensor system of claim 23 , wherein the electronic circuitry is configured to generate information responsive to the received information signals.
25. The sensor system of claim 24 , wherein the generated information includes at least one of a counter value, a trim setting value, a mode status, a channel setting, and an electronic circuitry identifier.
26. The sensor system of claim 24 , wherein the electronic circuitry is configured to provide to the device one or more response signals corresponding to the generated information.
27. The sensor system of claim 26 , wherein the one or more response signals comprise a plurality of unipolar pulses.
28. The sensor system of claim 23 , wherein the electronic circuitry comprises a line interface configured to receive the one or more information signals from the device.
29. The sensor system of claim 23 , wherein the one or more information signals comprise a plurality of bipolar pulses.
30. The sensor system of claim 29 , wherein the electronic circuitry is configured to decode a first pair of adjacent ones of the bipolar pulses as a first binary information unit.
31. The sensor system of claim 30 ,
wherein the electronic circuitry is configured to decode a second pair of adjacent ones of the bipolar pulses as a second binary information unit,
wherein the receipt of the first pair and the receipt of the second pair are separated by a time delay, and
wherein one or more other pulses of the bipolar pulses are received by the electronic circuitry over the time delay.
32. The sensor system of claim 31 , wherein the electronic circuitry is configured to ignore the one or more other pulses received over the time delay.
33. The sensor system of claim 32 , wherein the electronic circuitry is configured to generate information responsive to the receipt of the first pair and the receipt of the second pair but not the receipt of the one or more other pulses received over the time delay.
34. The sensor system of claim 23 , wherein the electronic circuitry comprises variable bias circuitry configured to provide a suitable amount of bias current responsive to the receipt of the one or more information signals.
35. The sensor system of claim 23 , further comprising the device, wherein the device is configured for implantation in a living body.
36. A sensor system comprising:
one or more sensors configured to sense one or more parameters and to provide one or more signals corresponding to the parameters; and
electronic circuitry configured to be coupled to a source and configured to receive electrical power from the source to:
receive the one or more signals from the one or more sensors; and
process the received one or more signals;
wherein the electronic circuitry is configured for implantation in a living body, and
wherein, upon the implantation of the electronic circuitry in the living body, the electronic circuitry is located external of the source.
37. The sensor system of claim 36 ,
wherein the electrical power is provided from the source to the electronic circuitry via one or more second signals.
38. The sensor system of claim 37 ,
wherein the one or more second signals comprise a plurality of pulses.
39. The sensor system of claim 37 ,
wherein the electronic circuitry comprises:
a storage device; and
a rectifier coupled with the storage device and coupled with a plurality of input/output lines to receive the one or more second signals,
wherein the rectifier is configured to store electrical power of the received one or more second signals at the storage device.
40. The sensor system of claim 39 , wherein the storage device comprises a capacitor.
41. The sensor system of claim 39 , further comprising a casing configured to encase the electronic circuitry.
42. The sensor system of claim 41 , wherein the casing is hermetically sealed.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US12/419,188 US20090203979A1 (en) | 2001-10-23 | 2009-04-06 | Implantable sensor electrodes and electronic circuitry |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US33565201P | 2001-10-23 | 2001-10-23 | |
US10/034,338 US6809507B2 (en) | 2001-10-23 | 2001-12-28 | Implantable sensor electrodes and electronic circuitry |
US10/973,525 US7525298B2 (en) | 2001-10-23 | 2004-10-25 | Implantable sensor electrodes and electronic circuitry |
US12/419,188 US20090203979A1 (en) | 2001-10-23 | 2009-04-06 | Implantable sensor electrodes and electronic circuitry |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/973,525 Division US7525298B2 (en) | 2001-10-23 | 2004-10-25 | Implantable sensor electrodes and electronic circuitry |
Publications (1)
Publication Number | Publication Date |
---|---|
US20090203979A1 true US20090203979A1 (en) | 2009-08-13 |
Family
ID=26710831
Family Applications (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/034,338 Expired - Lifetime US6809507B2 (en) | 2001-10-23 | 2001-12-28 | Implantable sensor electrodes and electronic circuitry |
US10/973,525 Active 2024-06-01 US7525298B2 (en) | 2001-10-23 | 2004-10-25 | Implantable sensor electrodes and electronic circuitry |
US12/419,188 Abandoned US20090203979A1 (en) | 2001-10-23 | 2009-04-06 | Implantable sensor electrodes and electronic circuitry |
Family Applications Before (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/034,338 Expired - Lifetime US6809507B2 (en) | 2001-10-23 | 2001-12-28 | Implantable sensor electrodes and electronic circuitry |
US10/973,525 Active 2024-06-01 US7525298B2 (en) | 2001-10-23 | 2004-10-25 | Implantable sensor electrodes and electronic circuitry |
Country Status (5)
Country | Link |
---|---|
US (3) | US6809507B2 (en) |
EP (1) | EP1446674B1 (en) |
JP (1) | JP4644425B2 (en) |
CA (1) | CA2463907C (en) |
WO (1) | WO2003036310A1 (en) |
Families Citing this family (207)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050075682A1 (en) * | 1997-02-26 | 2005-04-07 | Schulman Joseph H. | Neural device for sensing temperature |
US6001067A (en) | 1997-03-04 | 1999-12-14 | Shults; Mark C. | Device and method for determining analyte levels |
US20050033132A1 (en) | 1997-03-04 | 2005-02-10 | Shults Mark C. | Analyte measuring device |
US7657297B2 (en) * | 2004-05-03 | 2010-02-02 | Dexcom, Inc. | Implantable analyte sensor |
US7192450B2 (en) * | 2003-05-21 | 2007-03-20 | Dexcom, Inc. | Porous membranes for use with implantable devices |
US7899511B2 (en) | 2004-07-13 | 2011-03-01 | Dexcom, Inc. | Low oxygen in vivo analyte sensor |
US6741877B1 (en) * | 1997-03-04 | 2004-05-25 | Dexcom, Inc. | Device and method for determining analyte levels |
US20030036746A1 (en) | 2001-08-16 | 2003-02-20 | Avi Penner | Devices for intrabody delivery of molecules and systems and methods utilizing same |
US9066695B2 (en) | 1998-04-30 | 2015-06-30 | Abbott Diabetes Care Inc. | Analyte monitoring device and methods of use |
US8465425B2 (en) | 1998-04-30 | 2013-06-18 | Abbott Diabetes Care Inc. | Analyte monitoring device and methods of use |
US8480580B2 (en) | 1998-04-30 | 2013-07-09 | Abbott Diabetes Care Inc. | Analyte monitoring device and methods of use |
US8688188B2 (en) | 1998-04-30 | 2014-04-01 | Abbott Diabetes Care Inc. | Analyte monitoring device and methods of use |
US8974386B2 (en) | 1998-04-30 | 2015-03-10 | Abbott Diabetes Care Inc. | Analyte monitoring device and methods of use |
US6175752B1 (en) | 1998-04-30 | 2001-01-16 | Therasense, Inc. | Analyte monitoring device and methods of use |
US6949816B2 (en) | 2003-04-21 | 2005-09-27 | Motorola, Inc. | Semiconductor component having first surface area for electrically coupling to a semiconductor chip and second surface area for electrically coupling to a substrate, and method of manufacturing same |
US8346337B2 (en) | 1998-04-30 | 2013-01-01 | Abbott Diabetes Care Inc. | Analyte monitoring device and methods of use |
US6330464B1 (en) | 1998-08-26 | 2001-12-11 | Sensors For Medicine & Science | Optical-based sensing devices |
US7553280B2 (en) * | 2000-06-29 | 2009-06-30 | Sensors For Medicine And Science, Inc. | Implanted sensor processing system and method |
US7198603B2 (en) * | 2003-04-14 | 2007-04-03 | Remon Medical Technologies, Inc. | Apparatus and methods using acoustic telemetry for intrabody communications |
US7024248B2 (en) * | 2000-10-16 | 2006-04-04 | Remon Medical Technologies Ltd | Systems and methods for communicating with implantable devices |
US6560471B1 (en) | 2001-01-02 | 2003-05-06 | Therasense, Inc. | Analyte monitoring device and methods of use |
EP1397068A2 (en) | 2001-04-02 | 2004-03-17 | Therasense, Inc. | Blood glucose tracking apparatus and methods |
CA2445127C (en) * | 2001-05-04 | 2011-12-13 | Sensors For Medicine And Science, Inc. | Electro-optical sensing device with reference channel |
US20030032874A1 (en) | 2001-07-27 | 2003-02-13 | Dexcom, Inc. | Sensor head for use with implantable devices |
US6702857B2 (en) | 2001-07-27 | 2004-03-09 | Dexcom, Inc. | Membrane for use with implantable devices |
US6809507B2 (en) * | 2001-10-23 | 2004-10-26 | Medtronic Minimed, Inc. | Implantable sensor electrodes and electronic circuitry |
US7247162B1 (en) | 2002-01-14 | 2007-07-24 | Edwards Lifesciences Corporation | Direct access atherectomy devices |
US9282925B2 (en) | 2002-02-12 | 2016-03-15 | Dexcom, Inc. | Systems and methods for replacing signal artifacts in a glucose sensor data stream |
US7613491B2 (en) | 2002-05-22 | 2009-11-03 | Dexcom, Inc. | Silicone based membranes for use in implantable glucose sensors |
US8260393B2 (en) | 2003-07-25 | 2012-09-04 | Dexcom, Inc. | Systems and methods for replacing signal data artifacts in a glucose sensor data stream |
US10022078B2 (en) | 2004-07-13 | 2018-07-17 | Dexcom, Inc. | Analyte sensor |
US8010174B2 (en) | 2003-08-22 | 2011-08-30 | Dexcom, Inc. | Systems and methods for replacing signal artifacts in a glucose sensor data stream |
GB2385132A (en) * | 2002-02-12 | 2003-08-13 | Seiko Epson Corp | A capacitance sensor |
US9247901B2 (en) | 2003-08-22 | 2016-02-02 | Dexcom, Inc. | Systems and methods for replacing signal artifacts in a glucose sensor data stream |
US8364229B2 (en) | 2003-07-25 | 2013-01-29 | Dexcom, Inc. | Analyte sensors having a signal-to-noise ratio substantially unaffected by non-constant noise |
US7226978B2 (en) | 2002-05-22 | 2007-06-05 | Dexcom, Inc. | Techniques to improve polyurethane membranes for implantable glucose sensors |
US20060258761A1 (en) * | 2002-05-22 | 2006-11-16 | Robert Boock | Silicone based membranes for use in implantable glucose sensors |
AU2003303597A1 (en) | 2002-12-31 | 2004-07-29 | Therasense, Inc. | Continuous glucose monitoring system and methods of use |
US7134999B2 (en) | 2003-04-04 | 2006-11-14 | Dexcom, Inc. | Optimized sensor geometry for an implantable glucose sensor |
EP1620714B1 (en) * | 2003-04-15 | 2014-03-12 | Senseonics, Incorporated | System and method for attenuating the effect of ambient light on an optical sensor |
ES2737835T3 (en) | 2003-04-23 | 2020-01-16 | Valeritas Inc | Hydraulically driven pump for long-term medication administration |
US7875293B2 (en) | 2003-05-21 | 2011-01-25 | Dexcom, Inc. | Biointerface membranes incorporating bioactive agents |
US8066639B2 (en) | 2003-06-10 | 2011-11-29 | Abbott Diabetes Care Inc. | Glucose measuring device for use in personal area network |
US7366556B2 (en) | 2003-12-05 | 2008-04-29 | Dexcom, Inc. | Dual electrode system for a continuous analyte sensor |
JP2007500336A (en) * | 2003-07-25 | 2007-01-11 | デックスコム・インコーポレーテッド | Electrode system for electrochemical sensors |
WO2005019795A2 (en) * | 2003-07-25 | 2005-03-03 | Dexcom, Inc. | Electrochemical sensors including electrode systems with increased oxygen generation |
US7460898B2 (en) * | 2003-12-05 | 2008-12-02 | Dexcom, Inc. | Dual electrode system for a continuous analyte sensor |
US8282549B2 (en) | 2003-12-09 | 2012-10-09 | Dexcom, Inc. | Signal processing for continuous analyte sensor |
US7467003B2 (en) * | 2003-12-05 | 2008-12-16 | Dexcom, Inc. | Dual electrode system for a continuous analyte sensor |
US7424318B2 (en) | 2003-12-05 | 2008-09-09 | Dexcom, Inc. | Dual electrode system for a continuous analyte sensor |
US8423113B2 (en) | 2003-07-25 | 2013-04-16 | Dexcom, Inc. | Systems and methods for processing sensor data |
WO2005012871A2 (en) * | 2003-07-25 | 2005-02-10 | Dexcom, Inc. | Increasing bias for oxygen production in an electrode system |
WO2007120442A2 (en) * | 2003-07-25 | 2007-10-25 | Dexcom, Inc. | Dual electrode system for a continuous analyte sensor |
US9763609B2 (en) | 2003-07-25 | 2017-09-19 | Dexcom, Inc. | Analyte sensors having a signal-to-noise ratio substantially unaffected by non-constant noise |
US20190357827A1 (en) | 2003-08-01 | 2019-11-28 | Dexcom, Inc. | Analyte sensor |
US8160669B2 (en) | 2003-08-01 | 2012-04-17 | Dexcom, Inc. | Transcutaneous analyte sensor |
US8275437B2 (en) | 2003-08-01 | 2012-09-25 | Dexcom, Inc. | Transcutaneous analyte sensor |
US8369919B2 (en) | 2003-08-01 | 2013-02-05 | Dexcom, Inc. | Systems and methods for processing sensor data |
US7774145B2 (en) | 2003-08-01 | 2010-08-10 | Dexcom, Inc. | Transcutaneous analyte sensor |
US7494465B2 (en) | 2004-07-13 | 2009-02-24 | Dexcom, Inc. | Transcutaneous analyte sensor |
US20100168657A1 (en) | 2003-08-01 | 2010-07-01 | Dexcom, Inc. | System and methods for processing analyte sensor data |
US7933639B2 (en) | 2003-08-01 | 2011-04-26 | Dexcom, Inc. | System and methods for processing analyte sensor data |
US8886273B2 (en) | 2003-08-01 | 2014-11-11 | Dexcom, Inc. | Analyte sensor |
US7276029B2 (en) | 2003-08-01 | 2007-10-02 | Dexcom, Inc. | System and methods for processing analyte sensor data |
US7591801B2 (en) | 2004-02-26 | 2009-09-22 | Dexcom, Inc. | Integrated delivery device for continuous glucose sensor |
US8761856B2 (en) | 2003-08-01 | 2014-06-24 | Dexcom, Inc. | System and methods for processing analyte sensor data |
US9135402B2 (en) | 2007-12-17 | 2015-09-15 | Dexcom, Inc. | Systems and methods for processing sensor data |
US7519408B2 (en) | 2003-11-19 | 2009-04-14 | Dexcom, Inc. | Integrated receiver for continuous analyte sensor |
US20140121989A1 (en) | 2003-08-22 | 2014-05-01 | Dexcom, Inc. | Systems and methods for processing analyte sensor data |
US7920906B2 (en) | 2005-03-10 | 2011-04-05 | Dexcom, Inc. | System and methods for processing analyte sensor data for sensor calibration |
US20050090607A1 (en) * | 2003-10-28 | 2005-04-28 | Dexcom, Inc. | Silicone composition for biocompatible membrane |
US9247900B2 (en) | 2004-07-13 | 2016-02-02 | Dexcom, Inc. | Analyte sensor |
US8364231B2 (en) | 2006-10-04 | 2013-01-29 | Dexcom, Inc. | Analyte sensor |
EP2239567B1 (en) | 2003-12-05 | 2015-09-02 | DexCom, Inc. | Calibration techniques for a continuous analyte sensor |
US8774886B2 (en) | 2006-10-04 | 2014-07-08 | Dexcom, Inc. | Analyte sensor |
US11633133B2 (en) | 2003-12-05 | 2023-04-25 | Dexcom, Inc. | Dual electrode system for a continuous analyte sensor |
US8287453B2 (en) | 2003-12-05 | 2012-10-16 | Dexcom, Inc. | Analyte sensor |
US8423114B2 (en) | 2006-10-04 | 2013-04-16 | Dexcom, Inc. | Dual electrode system for a continuous analyte sensor |
EP1718198A4 (en) | 2004-02-17 | 2008-06-04 | Therasense Inc | Method and system for providing data communication in continuous glucose monitoring and management system |
US8808228B2 (en) | 2004-02-26 | 2014-08-19 | Dexcom, Inc. | Integrated medicament delivery device for use with continuous analyte sensor |
US8792955B2 (en) | 2004-05-03 | 2014-07-29 | Dexcom, Inc. | Transcutaneous analyte sensor |
WO2006014425A1 (en) | 2004-07-02 | 2006-02-09 | Biovalve Technologies, Inc. | Methods and devices for delivering glp-1 and uses thereof |
US7640048B2 (en) | 2004-07-13 | 2009-12-29 | Dexcom, Inc. | Analyte sensor |
US8565848B2 (en) | 2004-07-13 | 2013-10-22 | Dexcom, Inc. | Transcutaneous analyte sensor |
US7783333B2 (en) | 2004-07-13 | 2010-08-24 | Dexcom, Inc. | Transcutaneous medical device with variable stiffness |
US20060020192A1 (en) | 2004-07-13 | 2006-01-26 | Dexcom, Inc. | Transcutaneous analyte sensor |
WO2006026768A1 (en) | 2004-09-01 | 2006-03-09 | Microchips, Inc. | Multi-cap reservoir devices for controlled release or exposure of reservoir contents |
US8271093B2 (en) | 2004-09-17 | 2012-09-18 | Cardiac Pacemakers, Inc. | Systems and methods for deriving relative physiologic measurements using a backend computing system |
US7813808B1 (en) | 2004-11-24 | 2010-10-12 | Remon Medical Technologies Ltd | Implanted sensor system with optimized operational and sensing parameters |
US8133178B2 (en) | 2006-02-22 | 2012-03-13 | Dexcom, Inc. | Analyte sensor |
US7308292B2 (en) | 2005-04-15 | 2007-12-11 | Sensors For Medicine And Science, Inc. | Optical-based sensing devices |
US8112240B2 (en) | 2005-04-29 | 2012-02-07 | Abbott Diabetes Care Inc. | Method and apparatus for providing leak detection in data monitoring and management systems |
US7742815B2 (en) | 2005-09-09 | 2010-06-22 | Cardiac Pacemakers, Inc. | Using implanted sensors for feedback control of implanted medical devices |
US9168383B2 (en) | 2005-10-14 | 2015-10-27 | Pacesetter, Inc. | Leadless cardiac pacemaker with conducted communication |
EP2471451A1 (en) | 2005-10-14 | 2012-07-04 | Nanostim, Inc. | Leadless cardiac pacemaker and system |
US7766829B2 (en) | 2005-11-04 | 2010-08-03 | Abbott Diabetes Care Inc. | Method and system for providing basal profile modification in analyte monitoring and management systems |
US7774038B2 (en) | 2005-12-30 | 2010-08-10 | Medtronic Minimed, Inc. | Real-time self-calibrating sensor system and method |
US9757061B2 (en) | 2006-01-17 | 2017-09-12 | Dexcom, Inc. | Low oxygen in vivo analyte sensor |
WO2007097754A1 (en) | 2006-02-22 | 2007-08-30 | Dexcom, Inc. | Analyte sensor |
EP4218548A1 (en) | 2006-03-09 | 2023-08-02 | Dexcom, Inc. | Systems and methods for processing analyte sensor data |
EP1991110B1 (en) | 2006-03-09 | 2018-11-07 | DexCom, Inc. | Systems and methods for processing analyte sensor data |
AU2007233231B2 (en) | 2006-03-30 | 2011-02-24 | Mannkind Corporation | Multi-cartridge fluid delivery device |
US7620438B2 (en) | 2006-03-31 | 2009-11-17 | Abbott Diabetes Care Inc. | Method and system for powering an electronic device |
US8226891B2 (en) | 2006-03-31 | 2012-07-24 | Abbott Diabetes Care Inc. | Analyte monitoring devices and methods therefor |
US7920907B2 (en) | 2006-06-07 | 2011-04-05 | Abbott Diabetes Care Inc. | Analyte monitoring system and method |
US7908334B2 (en) * | 2006-07-21 | 2011-03-15 | Cardiac Pacemakers, Inc. | System and method for addressing implantable devices |
US7955268B2 (en) | 2006-07-21 | 2011-06-07 | Cardiac Pacemakers, Inc. | Multiple sensor deployment |
US20080077440A1 (en) * | 2006-09-26 | 2008-03-27 | Remon Medical Technologies, Ltd | Drug dispenser responsive to physiological parameters |
TWI317015B (en) * | 2006-10-02 | 2009-11-11 | Eps Bio Technology Corp | Biosensing device |
US7831287B2 (en) | 2006-10-04 | 2010-11-09 | Dexcom, Inc. | Dual electrode system for a continuous analyte sensor |
US8930203B2 (en) | 2007-02-18 | 2015-01-06 | Abbott Diabetes Care Inc. | Multi-function analyte test device and methods therefor |
US8732188B2 (en) | 2007-02-18 | 2014-05-20 | Abbott Diabetes Care Inc. | Method and system for providing contextual based medication dosage determination |
US8123686B2 (en) | 2007-03-01 | 2012-02-28 | Abbott Diabetes Care Inc. | Method and apparatus for providing rolling data in communication systems |
US7928850B2 (en) | 2007-05-08 | 2011-04-19 | Abbott Diabetes Care Inc. | Analyte monitoring system and methods |
US8665091B2 (en) | 2007-05-08 | 2014-03-04 | Abbott Diabetes Care Inc. | Method and device for determining elapsed sensor life |
US8456301B2 (en) | 2007-05-08 | 2013-06-04 | Abbott Diabetes Care Inc. | Analyte monitoring system and methods |
US8461985B2 (en) | 2007-05-08 | 2013-06-11 | Abbott Diabetes Care Inc. | Analyte monitoring system and methods |
US20200037875A1 (en) | 2007-05-18 | 2020-02-06 | Dexcom, Inc. | Analyte sensors having a signal-to-noise ratio substantially unaffected by non-constant noise |
EP2152350A4 (en) | 2007-06-08 | 2013-03-27 | Dexcom Inc | Integrated medicament delivery device for use with continuous analyte sensor |
WO2008154145A1 (en) * | 2007-06-14 | 2008-12-18 | Cardiac Pacemakers, Inc. | Intracorporeal pressure measurement devices and methods |
US20120046533A1 (en) | 2007-08-29 | 2012-02-23 | Medtronic Minimed, Inc. | Combined sensor and infusion sets |
US9968742B2 (en) | 2007-08-29 | 2018-05-15 | Medtronic Minimed, Inc. | Combined sensor and infusion set using separated sites |
EP4098177A1 (en) | 2007-10-09 | 2022-12-07 | DexCom, Inc. | Integrated insulin delivery system with continuous glucose sensor |
US8000918B2 (en) | 2007-10-23 | 2011-08-16 | Edwards Lifesciences Corporation | Monitoring and compensating for temperature-related error in an electrochemical sensor |
US8417312B2 (en) | 2007-10-25 | 2013-04-09 | Dexcom, Inc. | Systems and methods for processing sensor data |
US9839395B2 (en) | 2007-12-17 | 2017-12-12 | Dexcom, Inc. | Systems and methods for processing sensor data |
US8041431B2 (en) * | 2008-01-07 | 2011-10-18 | Cardiac Pacemakers, Inc. | System and method for in situ trimming of oscillators in a pair of implantable medical devices |
USD612279S1 (en) | 2008-01-18 | 2010-03-23 | Lifescan Scotland Limited | User interface in an analyte meter |
US8360984B2 (en) * | 2008-01-28 | 2013-01-29 | Cardiomems, Inc. | Hypertension system and method |
US8301262B2 (en) * | 2008-02-06 | 2012-10-30 | Cardiac Pacemakers, Inc. | Direct inductive/acoustic converter for implantable medical device |
EP2242538B1 (en) | 2008-02-11 | 2016-04-06 | Cardiac Pacemakers, Inc. | Methods of monitoring hemodynamic status for ryhthm discrimination within the heart |
WO2009102640A1 (en) | 2008-02-12 | 2009-08-20 | Cardiac Pacemakers, Inc. | Systems and methods for controlling wireless signal transfers between ultrasound-enabled medical devices |
CA2715628A1 (en) | 2008-02-21 | 2009-08-27 | Dexcom, Inc. | Systems and methods for processing, transmitting and displaying sensor data |
IL197532A0 (en) | 2008-03-21 | 2009-12-24 | Lifescan Scotland Ltd | Analyte testing method and system |
US20090242399A1 (en) * | 2008-03-25 | 2009-10-01 | Dexcom, Inc. | Analyte sensor |
USD611151S1 (en) | 2008-06-10 | 2010-03-02 | Lifescan Scotland, Ltd. | Test meter |
WO2010019326A1 (en) | 2008-08-14 | 2010-02-18 | Cardiac Pacemakers, Inc. | Performance assessment and adaptation of an acoustic communication link |
WO2010027771A1 (en) | 2008-08-27 | 2010-03-11 | Edwards Lifesciences Corporation | Analyte sensor |
USD611372S1 (en) | 2008-09-19 | 2010-03-09 | Lifescan Scotland Limited | Analyte test meter |
US8591423B2 (en) | 2008-10-10 | 2013-11-26 | Cardiac Pacemakers, Inc. | Systems and methods for determining cardiac output using pulmonary artery pressure measurements |
WO2010059291A1 (en) | 2008-11-19 | 2010-05-27 | Cardiac Pacemakers, Inc. | Assessment of pulmonary vascular resistance via pulmonary artery pressure |
US8103456B2 (en) | 2009-01-29 | 2012-01-24 | Abbott Diabetes Care Inc. | Method and device for early signal attenuation detection using blood glucose measurements |
US8527068B2 (en) | 2009-02-02 | 2013-09-03 | Nanostim, Inc. | Leadless cardiac pacemaker with secondary fixation capability |
EP2410910A4 (en) | 2009-03-27 | 2014-10-15 | Dexcom Inc | Methods and systems for promoting glucose management |
US9226701B2 (en) | 2009-04-28 | 2016-01-05 | Abbott Diabetes Care Inc. | Error detection in critical repeating data in a wireless sensor system |
WO2010138856A1 (en) | 2009-05-29 | 2010-12-02 | Abbott Diabetes Care Inc. | Medical device antenna systems having external antenna configurations |
US20100324378A1 (en) * | 2009-06-17 | 2010-12-23 | Tran Binh C | Physiologic signal monitoring using ultrasound signals from implanted devices |
EP2448485B1 (en) | 2009-07-02 | 2021-08-25 | Dexcom, Inc. | Analyte sensor |
WO2011026148A1 (en) | 2009-08-31 | 2011-03-03 | Abbott Diabetes Care Inc. | Analyte monitoring system and methods for managing power and noise |
WO2011026147A1 (en) | 2009-08-31 | 2011-03-03 | Abbott Diabetes Care Inc. | Analyte signal processing device and methods |
US9320461B2 (en) | 2009-09-29 | 2016-04-26 | Abbott Diabetes Care Inc. | Method and apparatus for providing notification function in analyte monitoring systems |
US20110082356A1 (en) | 2009-10-01 | 2011-04-07 | Medtronic Minimed, Inc. | Analyte sensor apparatuses having interference rejection membranes and methods for making and using them |
US20110288388A1 (en) | 2009-11-20 | 2011-11-24 | Medtronic Minimed, Inc. | Multi-conductor lead configurations useful with medical device systems and methods for making and using them |
US8660628B2 (en) | 2009-12-21 | 2014-02-25 | Medtronic Minimed, Inc. | Analyte sensors comprising blended membrane compositions and methods for making and using them |
US10448872B2 (en) | 2010-03-16 | 2019-10-22 | Medtronic Minimed, Inc. | Analyte sensor apparatuses having improved electrode configurations and methods for making and using them |
US9215995B2 (en) | 2010-06-23 | 2015-12-22 | Medtronic Minimed, Inc. | Sensor systems having multiple probes and electrode arrays |
WO2012048168A2 (en) * | 2010-10-07 | 2012-04-12 | Abbott Diabetes Care Inc. | Analyte monitoring devices and methods |
CN103249452A (en) | 2010-10-12 | 2013-08-14 | 内诺斯蒂姆股份有限公司 | Temperature sensor for a leadless cardiac pacemaker |
US9060692B2 (en) | 2010-10-12 | 2015-06-23 | Pacesetter, Inc. | Temperature sensor for a leadless cardiac pacemaker |
WO2012051235A1 (en) | 2010-10-13 | 2012-04-19 | Nanostim, Inc. | Leadless cardiac pacemaker with anti-unscrewing feature |
US8615310B2 (en) | 2010-12-13 | 2013-12-24 | Pacesetter, Inc. | Delivery catheter systems and methods |
CN103402578B (en) | 2010-12-13 | 2016-03-02 | 内诺斯蒂姆股份有限公司 | Pacemaker recovery system and method |
US9242102B2 (en) | 2010-12-20 | 2016-01-26 | Pacesetter, Inc. | Leadless pacemaker with radial fixation mechanism |
US8509899B2 (en) | 2010-12-23 | 2013-08-13 | Medtronic, Inc. | Multi-electrode implantable systems and assemblies thereof |
WO2012142502A2 (en) | 2011-04-15 | 2012-10-18 | Dexcom Inc. | Advanced analyte sensor calibration and error detection |
US9008744B2 (en) | 2011-05-06 | 2015-04-14 | Medtronic Minimed, Inc. | Method and apparatus for continuous analyte monitoring |
KR20140082642A (en) | 2011-07-26 | 2014-07-02 | 글리젠스 인코포레이티드 | Tissue implantable sensor with hermetically sealed housing |
WO2013067496A2 (en) | 2011-11-04 | 2013-05-10 | Nanostim, Inc. | Leadless cardiac pacemaker with integral battery and redundant welds |
JP6443802B2 (en) | 2011-11-07 | 2018-12-26 | アボット ダイアベティス ケア インコーポレイテッドAbbott Diabetes Care Inc. | Analyte monitoring apparatus and method |
US9493807B2 (en) | 2012-05-25 | 2016-11-15 | Medtronic Minimed, Inc. | Foldover sensors and methods for making and using them |
US20140012115A1 (en) | 2012-07-03 | 2014-01-09 | Medtronic Minimed, Inc. | Plasma deposited adhesion promoter layers for use with analyte sensors |
US10660550B2 (en) | 2015-12-29 | 2020-05-26 | Glysens Incorporated | Implantable sensor apparatus and methods |
US10561353B2 (en) | 2016-06-01 | 2020-02-18 | Glysens Incorporated | Biocompatible implantable sensor apparatus and methods |
WO2014022661A1 (en) | 2012-08-01 | 2014-02-06 | Nanostim, Inc. | Biostimulator circuit with flying cell |
US9968306B2 (en) | 2012-09-17 | 2018-05-15 | Abbott Diabetes Care Inc. | Methods and apparatuses for providing adverse condition notification with enhanced wireless communication range in analyte monitoring systems |
US10194840B2 (en) | 2012-12-06 | 2019-02-05 | Medtronic Minimed, Inc. | Microarray electrodes useful with analyte sensors and methods for making and using them |
EP2757352B1 (en) * | 2013-01-17 | 2015-11-18 | EM Microelectronic-Marin SA | Control system and management method of a sensor |
US10426383B2 (en) | 2013-01-22 | 2019-10-01 | Medtronic Minimed, Inc. | Muting glucose sensor oxygen response and reducing electrode edge growth with pulsed current plating |
US20150122647A1 (en) | 2013-11-07 | 2015-05-07 | Medtronic Minimed, Inc. | Enzyme matrices for use with ethylene oxide sterilization |
US10324058B2 (en) | 2016-04-28 | 2019-06-18 | Medtronic Minimed, Inc. | In-situ chemistry stack for continuous glucose sensors |
WO2017195035A1 (en) | 2016-05-10 | 2017-11-16 | Interface Biologics, Inc. | Implantable glucose sensors having a biostable surface |
US11298059B2 (en) | 2016-05-13 | 2022-04-12 | PercuSense, Inc. | Analyte sensor |
US11179078B2 (en) | 2016-06-06 | 2021-11-23 | Medtronic Minimed, Inc. | Polycarbonate urea/urethane polymers for use with analyte sensors |
US10638962B2 (en) | 2016-06-29 | 2020-05-05 | Glysens Incorporated | Bio-adaptable implantable sensor apparatus and methods |
US11134868B2 (en) | 2017-03-17 | 2021-10-05 | Medtronic Minimed, Inc. | Metal pillar device structures and methods for making and using them in electrochemical and/or electrocatalytic applications |
US10856784B2 (en) | 2017-06-30 | 2020-12-08 | Medtronic Minimed, Inc. | Sensor initialization methods for faster body sensor response |
US10638979B2 (en) | 2017-07-10 | 2020-05-05 | Glysens Incorporated | Analyte sensor data evaluation and error reduction apparatus and methods |
US11382540B2 (en) | 2017-10-24 | 2022-07-12 | Dexcom, Inc. | Pre-connected analyte sensors |
US11331022B2 (en) | 2017-10-24 | 2022-05-17 | Dexcom, Inc. | Pre-connected analyte sensors |
US11278668B2 (en) | 2017-12-22 | 2022-03-22 | Glysens Incorporated | Analyte sensor and medicant delivery data evaluation and error reduction apparatus and methods |
US11255839B2 (en) | 2018-01-04 | 2022-02-22 | Glysens Incorporated | Apparatus and methods for analyte sensor mismatch correction |
US20190223771A1 (en) | 2018-01-23 | 2019-07-25 | Medtronic Minimed, Inc. | Implantable polymer surfaces exhibiting reduced in vivo inflammatory responses |
US11186859B2 (en) | 2018-02-07 | 2021-11-30 | Medtronic Minimed, Inc. | Multilayer electrochemical analyte sensors and methods for making and using them |
US11583213B2 (en) | 2018-02-08 | 2023-02-21 | Medtronic Minimed, Inc. | Glucose sensor electrode design |
US11220735B2 (en) | 2018-02-08 | 2022-01-11 | Medtronic Minimed, Inc. | Methods for controlling physical vapor deposition metal film adhesion to substrates and surfaces |
CN112088217A (en) | 2018-05-16 | 2020-12-15 | 美敦力泌力美公司 | Thermostable glucose limiting membrane for glucose sensors |
US11718865B2 (en) | 2019-07-26 | 2023-08-08 | Medtronic Minimed, Inc. | Methods to improve oxygen delivery to implantable sensors |
US11523757B2 (en) | 2019-08-01 | 2022-12-13 | Medtronic Minimed, Inc. | Micro-pillar working electrodes design to reduce backflow of hydrogen peroxide in glucose sensor |
US20220031205A1 (en) | 2020-07-31 | 2022-02-03 | Medtronic Minimed, Inc. | Sensor identification and integrity check design |
US20220133190A1 (en) | 2020-10-29 | 2022-05-05 | Medtronic Minimed, Inc. | Glucose biosensors comprising direct electron transfer enzymes and methods of making and using them |
US20220240823A1 (en) | 2021-01-29 | 2022-08-04 | Medtronic Minimed, Inc. | Interference rejection membranes useful with analyte sensors |
US20220338768A1 (en) | 2021-04-09 | 2022-10-27 | Medtronic Minimed, Inc. | Hexamethyldisiloxane membranes for analyte sensors |
US20230053254A1 (en) | 2021-08-13 | 2023-02-16 | Medtronic Minimed, Inc. | Dry electrochemical impedance spectroscopy metrology for conductive chemical layers |
US20230113175A1 (en) | 2021-10-08 | 2023-04-13 | Medtronic Minimed, Inc. | Immunosuppressant releasing coatings |
US20230123613A1 (en) | 2021-10-14 | 2023-04-20 | Medtronic Minimed, Inc. | Sensors for 3-hydroxybutyrate detection |
US20230172497A1 (en) | 2021-12-02 | 2023-06-08 | Medtronic Minimed, Inc. | Ketone limiting membrane and dual layer membrane approach for ketone sensing |
US20240023849A1 (en) | 2022-07-20 | 2024-01-25 | Medtronic Minimed, Inc. | Acrylate hydrogel membrane for dual function of diffusion limiting membrane as well as attenuation to the foreign body response |
Citations (79)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3716059A (en) * | 1970-08-24 | 1973-02-13 | Cardiac Resuscitator Corp | Cardiac resuscitator |
US3728622A (en) * | 1971-09-28 | 1973-04-17 | C Williams | Method of and apparatus for measuring in situ the formation factor |
US3992665A (en) * | 1973-09-10 | 1976-11-16 | Preikschat F K | Electrical impedance measuring apparatus |
US4240438A (en) * | 1978-10-02 | 1980-12-23 | Wisconsin Alumni Research Foundation | Method for monitoring blood glucose levels and elements |
US4311151A (en) * | 1977-08-24 | 1982-01-19 | Bunji Hagihara | Oxygen measuring electrode assembly |
US4333377A (en) * | 1979-08-17 | 1982-06-08 | Acoustic Standards | Tone generation system for electronic musical instrument |
US4479796A (en) * | 1982-11-15 | 1984-10-30 | Medtronic, Inc. | Self-regenerating drug administration device |
US4484987A (en) * | 1983-05-19 | 1984-11-27 | The Regents Of The University Of California | Method and membrane applicable to implantable sensor |
US4533986A (en) * | 1983-10-31 | 1985-08-06 | General Electric Company | Compact electrical power supply for signal processing applications |
US4568335A (en) * | 1981-08-28 | 1986-02-04 | Markwell Medical Institute, Inc. | Device for the controlled infusion of medications |
US4628928A (en) * | 1982-08-09 | 1986-12-16 | Medtronic, Inc. | Robotic implantable medical device and/or component restoration system |
US4650547A (en) * | 1983-05-19 | 1987-03-17 | The Regents Of The University Of California | Method and membrane applicable to implantable sensor |
US4703756A (en) * | 1986-05-06 | 1987-11-03 | The Regents Of The University Of California | Complete glucose monitoring system with an implantable, telemetered sensor module |
US4757022A (en) * | 1986-04-15 | 1988-07-12 | Markwell Medical Institute, Inc. | Biological fluid measuring device |
US4771772A (en) * | 1982-08-09 | 1988-09-20 | Medtronic, Inc. | Robotic implantable medical device and/or component restoration system |
US4816713A (en) * | 1987-10-09 | 1989-03-28 | Change Jr Nicholas D | Piezoelectric sensor with FET amplified output |
US4890620A (en) * | 1985-09-20 | 1990-01-02 | The Regents Of The University Of California | Two-dimensional diffusion glucose substrate sensing electrode |
US4900405A (en) * | 1987-07-15 | 1990-02-13 | Sri International | Surface type microelectronic gas and vapor sensor |
US4911168A (en) * | 1989-01-13 | 1990-03-27 | Pacesetter Infusion, Ltd. | Method of screening and selecting intraperitoneal medication infusion pump candidates |
US4963245A (en) * | 1986-05-02 | 1990-10-16 | Ciba Corning Diagnostics Corp. | Unitary multiple electrode sensor |
US4994167A (en) * | 1986-04-15 | 1991-02-19 | Markwell Medical Institute, Inc. | Biological fluid measuring device |
US5040533A (en) * | 1989-12-29 | 1991-08-20 | Medical Engineering And Development Institute Incorporated | Implantable cardiovascular treatment device container for sensing a physiological parameter |
US5056421A (en) * | 1990-10-03 | 1991-10-15 | Zexek Corporation | Automobile air-conditioner |
US5066372A (en) * | 1986-05-02 | 1991-11-19 | Ciba Corning Diagnostics Corp. | Unitary multiple electrode sensor |
US5094951A (en) * | 1988-06-21 | 1992-03-10 | Chiron Corporation | Production of glucose oxidase in recombinant systems |
US5266688A (en) * | 1988-06-21 | 1993-11-30 | Chiron Corporation | Polynucleotide sequence for production of glucose oxidase in recombinant systems |
US5328460A (en) * | 1991-06-21 | 1994-07-12 | Pacesetter Infusion, Ltd. | Implantable medication infusion pump including self-contained acoustic fault detection apparatus |
US5394095A (en) * | 1990-03-27 | 1995-02-28 | Fife Gmbh | Sensor for strip of conductive material |
US5497772A (en) * | 1993-11-19 | 1996-03-12 | Alfred E. Mann Foundation For Scientific Research | Glucose monitoring system |
US5534025A (en) * | 1993-06-08 | 1996-07-09 | The Governors Of The University Of Alberta | Vascular bioartificial organ |
US5593852A (en) * | 1993-12-02 | 1997-01-14 | Heller; Adam | Subcutaneous glucose electrode |
US5667983A (en) * | 1994-10-24 | 1997-09-16 | Chiron Diagnostics Corporation | Reagents with enhanced performance in clinical diagnostic systems |
US5696314A (en) * | 1996-07-12 | 1997-12-09 | Chiron Diagnostics Corporation | Multilayer enzyme electrode membranes and methods of making same |
US5707502A (en) * | 1996-07-12 | 1998-01-13 | Chiron Diagnostics Corporation | Sensors for measuring analyte concentrations and methods of making same |
US5711868A (en) * | 1994-06-27 | 1998-01-27 | Chiron Diagnostics Corporatiion | Electrochemical sensors membrane |
US5728281A (en) * | 1995-11-27 | 1998-03-17 | Pacesetter Ab | Implantable medical device including an arrangement for measuring a blood property having a carbon reference electrode |
US5741319A (en) * | 1995-01-27 | 1998-04-21 | Medtronic, Inc. | Biocompatible medical lead |
US5741211A (en) * | 1995-10-26 | 1998-04-21 | Medtronic, Inc. | System and method for continuous monitoring of diabetes-related blood constituents |
US5773270A (en) * | 1991-03-12 | 1998-06-30 | Chiron Diagnostics Corporation | Three-layered membrane for use in an electrochemical sensor system |
US5791344A (en) * | 1993-11-19 | 1998-08-11 | Alfred E. Mann Foundation For Scientific Research | Patient monitoring system |
US5804048A (en) * | 1996-08-15 | 1998-09-08 | Via Medical Corporation | Electrode assembly for assaying glucose |
US5917346A (en) * | 1997-09-12 | 1999-06-29 | Alfred E. Mann Foundation | Low power current to frequency converter circuit for use in implantable sensors |
US5919216A (en) * | 1997-06-16 | 1999-07-06 | Medtronic, Inc. | System and method for enhancement of glucose production by stimulation of pancreatic beta cells |
US5932175A (en) * | 1996-09-25 | 1999-08-03 | Via Medical Corporation | Sensor apparatus for use in measuring a parameter of a fluid sample |
US5941906A (en) * | 1997-10-15 | 1999-08-24 | Medtronic, Inc. | Implantable, modular tissue stimulator |
US5985129A (en) * | 1989-12-14 | 1999-11-16 | The Regents Of The University Of California | Method for increasing the service life of an implantable sensor |
US5989409A (en) * | 1995-09-11 | 1999-11-23 | Cygnus, Inc. | Method for glucose sensing |
US5992211A (en) * | 1998-04-23 | 1999-11-30 | Medtronic, Inc. | Calibrated medical sensing catheter system |
US5999849A (en) * | 1997-09-12 | 1999-12-07 | Alfred E. Mann Foundation | Low power rectifier circuit for implantable medical device |
US5999848A (en) * | 1997-09-12 | 1999-12-07 | Alfred E. Mann Foundation | Daisy chainable sensors and stimulators for implantation in living tissue |
US6001067A (en) * | 1997-03-04 | 1999-12-14 | Shults; Mark C. | Device and method for determining analyte levels |
US6002954A (en) * | 1995-11-22 | 1999-12-14 | The Regents Of The University Of California | Detection of biological molecules using boronate-based chemical amplification and optical sensors |
US6027479A (en) * | 1998-02-27 | 2000-02-22 | Via Medical Corporation | Medical apparatus incorporating pressurized supply of storage liquid |
US6037595A (en) * | 1995-10-13 | 2000-03-14 | Digirad Corporation | Radiation detector with shielding electrode |
US6049727A (en) * | 1996-07-08 | 2000-04-11 | Animas Corporation | Implantable sensor and system for in vivo measurement and control of fluid constituent levels |
USD424696S (en) * | 1999-05-06 | 2000-05-09 | Therasense, Inc. | Glucose sensor |
US6067474A (en) * | 1997-08-01 | 2000-05-23 | Advanced Bionics Corporation | Implantable device with improved battery recharging and powering configuration |
USD426638S (en) * | 1999-05-06 | 2000-06-13 | Therasense, Inc. | Glucose sensor buttons |
US6088608A (en) * | 1997-10-20 | 2000-07-11 | Alfred E. Mann Foundation | Electrochemical sensor and integrity tests therefor |
US6093167A (en) * | 1997-06-16 | 2000-07-25 | Medtronic, Inc. | System for pancreatic stimulation and glucose measurement |
US6103033A (en) * | 1998-03-04 | 2000-08-15 | Therasense, Inc. | Process for producing an electrochemical biosensor |
US6120676A (en) * | 1997-02-06 | 2000-09-19 | Therasense, Inc. | Method of using a small volume in vitro analyte sensor |
US6122536A (en) * | 1995-07-06 | 2000-09-19 | Animas Corporation | Implantable sensor and system for measurement and control of blood constituent levels |
US6125290A (en) * | 1998-10-30 | 2000-09-26 | Medtronic, Inc. | Tissue overgrowth detector for implantable medical device |
US6125291A (en) * | 1998-10-30 | 2000-09-26 | Medtronic, Inc. | Light barrier for medical electrical lead oxygen sensor |
US6134459A (en) * | 1998-10-30 | 2000-10-17 | Medtronic, Inc. | Light focusing apparatus for medical electrical lead oxygen sensor |
US6144866A (en) * | 1998-10-30 | 2000-11-07 | Medtronic, Inc. | Multiple sensor assembly for medical electric lead |
US6159240A (en) * | 1998-08-31 | 2000-12-12 | Medtronic, Inc. | Rigid annuloplasty device that becomes compliant after implantation |
US6163723A (en) * | 1998-10-22 | 2000-12-19 | Medtronic, Inc. | Circuit and method for implantable dual sensor medical electrical lead |
WO2000076436A1 (en) * | 1999-06-11 | 2000-12-21 | Cochlear Limited | Stimulus output monitor and control circuit for electrical tissue stimulator |
US6175752B1 (en) * | 1998-04-30 | 2001-01-16 | Therasense, Inc. | Analyte monitoring device and methods of use |
US6198952B1 (en) * | 1998-10-30 | 2001-03-06 | Medtronic, Inc. | Multiple lens oxygen sensor for medical electrical lead |
US6201980B1 (en) * | 1998-10-05 | 2001-03-13 | The Regents Of The University Of California | Implantable medical sensor system |
US6248080B1 (en) * | 1997-09-03 | 2001-06-19 | Medtronic, Inc. | Intracranial monitoring and therapy delivery control device, system and method |
US6251260B1 (en) * | 1998-08-24 | 2001-06-26 | Therasense, Inc. | Potentiometric sensors for analytic determination |
US6261280B1 (en) * | 1999-03-22 | 2001-07-17 | Medtronic, Inc | Method of obtaining a measure of blood glucose |
US6268161B1 (en) * | 1997-09-30 | 2001-07-31 | M-Biotech, Inc. | Biosensor |
US20030057970A1 (en) * | 2000-04-07 | 2003-03-27 | Yasunori Shiraki | Analyzer and method of testing analyzer |
US6809507B2 (en) * | 2001-10-23 | 2004-10-26 | Medtronic Minimed, Inc. | Implantable sensor electrodes and electronic circuitry |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5931326B2 (en) * | 1977-10-22 | 1984-08-01 | 文二 萩原 | Electrode device for oxygen measurement |
JPS5931326A (en) | 1982-08-15 | 1984-02-20 | Nippon Telegr & Teleph Corp <Ntt> | Submarine cable burying machine |
JPS61128945A (en) * | 1984-11-28 | 1986-06-17 | 住友電気工業株式会社 | Subcataneous blood gas sensor |
US4972835A (en) * | 1989-05-19 | 1990-11-27 | Ventritex, Inc. | Implantable cardiac defibrillator employing an improved sensing system with non-binary gain changes |
US5137022A (en) * | 1990-07-13 | 1992-08-11 | Cook Pacemaker Corporation | Synchronous telemetry system and method for an implantable medical device |
US5264103A (en) | 1991-10-18 | 1993-11-23 | Matsushita Electric Industrial Co., Ltd. | Biosensor and a method for measuring a concentration of a substrate in a sample |
US5556421A (en) * | 1995-02-22 | 1996-09-17 | Intermedics, Inc. | Implantable medical device with enclosed physiological parameter sensors or telemetry link |
US6159241A (en) * | 1997-04-01 | 2000-12-12 | Joseph Y. Lee | Method and apparatus for adjusting corneal curvature using multiple removable corneal implants |
US6368274B1 (en) | 1999-07-01 | 2002-04-09 | Medtronic Minimed, Inc. | Reusable analyte sensor site and method of using the same |
JP2004507283A (en) * | 2000-04-22 | 2004-03-11 | エム−バイオテック インコーポレイテッド | Hydrogel biosensor and health alarm system based on biosensor (HYDROGELBIOSENSORANDBIOENSENSOR-BASEDHEALTHALARMSYSTEM) |
-
2001
- 2001-12-28 US US10/034,338 patent/US6809507B2/en not_active Expired - Lifetime
-
2002
- 2002-09-27 WO PCT/US2002/030945 patent/WO2003036310A1/en active Application Filing
- 2002-09-27 CA CA2463907A patent/CA2463907C/en not_active Expired - Fee Related
- 2002-09-27 EP EP02773649.5A patent/EP1446674B1/en not_active Expired - Lifetime
- 2002-09-27 JP JP2003538755A patent/JP4644425B2/en not_active Expired - Fee Related
-
2004
- 2004-10-25 US US10/973,525 patent/US7525298B2/en active Active
-
2009
- 2009-04-06 US US12/419,188 patent/US20090203979A1/en not_active Abandoned
Patent Citations (86)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3716059A (en) * | 1970-08-24 | 1973-02-13 | Cardiac Resuscitator Corp | Cardiac resuscitator |
US3728622A (en) * | 1971-09-28 | 1973-04-17 | C Williams | Method of and apparatus for measuring in situ the formation factor |
US3992665A (en) * | 1973-09-10 | 1976-11-16 | Preikschat F K | Electrical impedance measuring apparatus |
US4311151A (en) * | 1977-08-24 | 1982-01-19 | Bunji Hagihara | Oxygen measuring electrode assembly |
US4240438A (en) * | 1978-10-02 | 1980-12-23 | Wisconsin Alumni Research Foundation | Method for monitoring blood glucose levels and elements |
US4333377A (en) * | 1979-08-17 | 1982-06-08 | Acoustic Standards | Tone generation system for electronic musical instrument |
US4568335A (en) * | 1981-08-28 | 1986-02-04 | Markwell Medical Institute, Inc. | Device for the controlled infusion of medications |
US4628928A (en) * | 1982-08-09 | 1986-12-16 | Medtronic, Inc. | Robotic implantable medical device and/or component restoration system |
US4771772A (en) * | 1982-08-09 | 1988-09-20 | Medtronic, Inc. | Robotic implantable medical device and/or component restoration system |
US4479796A (en) * | 1982-11-15 | 1984-10-30 | Medtronic, Inc. | Self-regenerating drug administration device |
US4650547A (en) * | 1983-05-19 | 1987-03-17 | The Regents Of The University Of California | Method and membrane applicable to implantable sensor |
US4484987A (en) * | 1983-05-19 | 1984-11-27 | The Regents Of The University Of California | Method and membrane applicable to implantable sensor |
US4533986A (en) * | 1983-10-31 | 1985-08-06 | General Electric Company | Compact electrical power supply for signal processing applications |
US4890620A (en) * | 1985-09-20 | 1990-01-02 | The Regents Of The University Of California | Two-dimensional diffusion glucose substrate sensing electrode |
US4757022A (en) * | 1986-04-15 | 1988-07-12 | Markwell Medical Institute, Inc. | Biological fluid measuring device |
US4994167A (en) * | 1986-04-15 | 1991-02-19 | Markwell Medical Institute, Inc. | Biological fluid measuring device |
US5066372A (en) * | 1986-05-02 | 1991-11-19 | Ciba Corning Diagnostics Corp. | Unitary multiple electrode sensor |
US4963245A (en) * | 1986-05-02 | 1990-10-16 | Ciba Corning Diagnostics Corp. | Unitary multiple electrode sensor |
US4703756A (en) * | 1986-05-06 | 1987-11-03 | The Regents Of The University Of California | Complete glucose monitoring system with an implantable, telemetered sensor module |
US4900405A (en) * | 1987-07-15 | 1990-02-13 | Sri International | Surface type microelectronic gas and vapor sensor |
US4816713A (en) * | 1987-10-09 | 1989-03-28 | Change Jr Nicholas D | Piezoelectric sensor with FET amplified output |
US5094951A (en) * | 1988-06-21 | 1992-03-10 | Chiron Corporation | Production of glucose oxidase in recombinant systems |
US5266688A (en) * | 1988-06-21 | 1993-11-30 | Chiron Corporation | Polynucleotide sequence for production of glucose oxidase in recombinant systems |
US4911168A (en) * | 1989-01-13 | 1990-03-27 | Pacesetter Infusion, Ltd. | Method of screening and selecting intraperitoneal medication infusion pump candidates |
US5985129A (en) * | 1989-12-14 | 1999-11-16 | The Regents Of The University Of California | Method for increasing the service life of an implantable sensor |
US5040533A (en) * | 1989-12-29 | 1991-08-20 | Medical Engineering And Development Institute Incorporated | Implantable cardiovascular treatment device container for sensing a physiological parameter |
US5394095A (en) * | 1990-03-27 | 1995-02-28 | Fife Gmbh | Sensor for strip of conductive material |
US5056421A (en) * | 1990-10-03 | 1991-10-15 | Zexek Corporation | Automobile air-conditioner |
US5773270A (en) * | 1991-03-12 | 1998-06-30 | Chiron Diagnostics Corporation | Three-layered membrane for use in an electrochemical sensor system |
US5328460A (en) * | 1991-06-21 | 1994-07-12 | Pacesetter Infusion, Ltd. | Implantable medication infusion pump including self-contained acoustic fault detection apparatus |
US5534025A (en) * | 1993-06-08 | 1996-07-09 | The Governors Of The University Of Alberta | Vascular bioartificial organ |
US5497772A (en) * | 1993-11-19 | 1996-03-12 | Alfred E. Mann Foundation For Scientific Research | Glucose monitoring system |
US5660163A (en) * | 1993-11-19 | 1997-08-26 | Alfred E. Mann Foundation For Scientific Research | Glucose sensor assembly |
US5791344A (en) * | 1993-11-19 | 1998-08-11 | Alfred E. Mann Foundation For Scientific Research | Patient monitoring system |
US6162611A (en) * | 1993-12-02 | 2000-12-19 | E. Heller & Company | Subcutaneous glucose electrode |
US5965380A (en) * | 1993-12-02 | 1999-10-12 | E. Heller & Company | Subcutaneous glucose electrode |
US5593852A (en) * | 1993-12-02 | 1997-01-14 | Heller; Adam | Subcutaneous glucose electrode |
US5711868A (en) * | 1994-06-27 | 1998-01-27 | Chiron Diagnostics Corporatiion | Electrochemical sensors membrane |
US5770028A (en) * | 1994-06-27 | 1998-06-23 | Chiron Diagnostics Corporation | Glucose and lactate sensors |
US5667983A (en) * | 1994-10-24 | 1997-09-16 | Chiron Diagnostics Corporation | Reagents with enhanced performance in clinical diagnostic systems |
US5741319A (en) * | 1995-01-27 | 1998-04-21 | Medtronic, Inc. | Biocompatible medical lead |
US6122536A (en) * | 1995-07-06 | 2000-09-19 | Animas Corporation | Implantable sensor and system for measurement and control of blood constituent levels |
US5989409A (en) * | 1995-09-11 | 1999-11-23 | Cygnus, Inc. | Method for glucose sensing |
US6037595A (en) * | 1995-10-13 | 2000-03-14 | Digirad Corporation | Radiation detector with shielding electrode |
US5741211A (en) * | 1995-10-26 | 1998-04-21 | Medtronic, Inc. | System and method for continuous monitoring of diabetes-related blood constituents |
US6002954A (en) * | 1995-11-22 | 1999-12-14 | The Regents Of The University Of California | Detection of biological molecules using boronate-based chemical amplification and optical sensors |
US5728281A (en) * | 1995-11-27 | 1998-03-17 | Pacesetter Ab | Implantable medical device including an arrangement for measuring a blood property having a carbon reference electrode |
US6049727A (en) * | 1996-07-08 | 2000-04-11 | Animas Corporation | Implantable sensor and system for in vivo measurement and control of fluid constituent levels |
US5696314A (en) * | 1996-07-12 | 1997-12-09 | Chiron Diagnostics Corporation | Multilayer enzyme electrode membranes and methods of making same |
US5707502A (en) * | 1996-07-12 | 1998-01-13 | Chiron Diagnostics Corporation | Sensors for measuring analyte concentrations and methods of making same |
US5804048A (en) * | 1996-08-15 | 1998-09-08 | Via Medical Corporation | Electrode assembly for assaying glucose |
US5932175A (en) * | 1996-09-25 | 1999-08-03 | Via Medical Corporation | Sensor apparatus for use in measuring a parameter of a fluid sample |
US6120676A (en) * | 1997-02-06 | 2000-09-19 | Therasense, Inc. | Method of using a small volume in vitro analyte sensor |
US6001067A (en) * | 1997-03-04 | 1999-12-14 | Shults; Mark C. | Device and method for determining analyte levels |
US5919216A (en) * | 1997-06-16 | 1999-07-06 | Medtronic, Inc. | System and method for enhancement of glucose production by stimulation of pancreatic beta cells |
US6135978A (en) * | 1997-06-16 | 2000-10-24 | Medtronic, Inc. | System for pancreatic stimulation and glucose measurement |
US6093167A (en) * | 1997-06-16 | 2000-07-25 | Medtronic, Inc. | System for pancreatic stimulation and glucose measurement |
US6067474A (en) * | 1997-08-01 | 2000-05-23 | Advanced Bionics Corporation | Implantable device with improved battery recharging and powering configuration |
US6248080B1 (en) * | 1997-09-03 | 2001-06-19 | Medtronic, Inc. | Intracranial monitoring and therapy delivery control device, system and method |
US5917346A (en) * | 1997-09-12 | 1999-06-29 | Alfred E. Mann Foundation | Low power current to frequency converter circuit for use in implantable sensors |
US5999849A (en) * | 1997-09-12 | 1999-12-07 | Alfred E. Mann Foundation | Low power rectifier circuit for implantable medical device |
US5999848A (en) * | 1997-09-12 | 1999-12-07 | Alfred E. Mann Foundation | Daisy chainable sensors and stimulators for implantation in living tissue |
US6268161B1 (en) * | 1997-09-30 | 2001-07-31 | M-Biotech, Inc. | Biosensor |
US5941906A (en) * | 1997-10-15 | 1999-08-24 | Medtronic, Inc. | Implantable, modular tissue stimulator |
US6088608A (en) * | 1997-10-20 | 2000-07-11 | Alfred E. Mann Foundation | Electrochemical sensor and integrity tests therefor |
US6387048B1 (en) * | 1997-10-20 | 2002-05-14 | Alfred E. Mann Foundation | Implantable sensor and integrity tests therefor |
US6027479A (en) * | 1998-02-27 | 2000-02-22 | Via Medical Corporation | Medical apparatus incorporating pressurized supply of storage liquid |
US6103033A (en) * | 1998-03-04 | 2000-08-15 | Therasense, Inc. | Process for producing an electrochemical biosensor |
US5992211A (en) * | 1998-04-23 | 1999-11-30 | Medtronic, Inc. | Calibrated medical sensing catheter system |
US6175752B1 (en) * | 1998-04-30 | 2001-01-16 | Therasense, Inc. | Analyte monitoring device and methods of use |
US6251260B1 (en) * | 1998-08-24 | 2001-06-26 | Therasense, Inc. | Potentiometric sensors for analytic determination |
US6159240A (en) * | 1998-08-31 | 2000-12-12 | Medtronic, Inc. | Rigid annuloplasty device that becomes compliant after implantation |
US6201980B1 (en) * | 1998-10-05 | 2001-03-13 | The Regents Of The University Of California | Implantable medical sensor system |
US6163723A (en) * | 1998-10-22 | 2000-12-19 | Medtronic, Inc. | Circuit and method for implantable dual sensor medical electrical lead |
US6134459A (en) * | 1998-10-30 | 2000-10-17 | Medtronic, Inc. | Light focusing apparatus for medical electrical lead oxygen sensor |
US6144866A (en) * | 1998-10-30 | 2000-11-07 | Medtronic, Inc. | Multiple sensor assembly for medical electric lead |
US6125291A (en) * | 1998-10-30 | 2000-09-26 | Medtronic, Inc. | Light barrier for medical electrical lead oxygen sensor |
US6198952B1 (en) * | 1998-10-30 | 2001-03-06 | Medtronic, Inc. | Multiple lens oxygen sensor for medical electrical lead |
US6125290A (en) * | 1998-10-30 | 2000-09-26 | Medtronic, Inc. | Tissue overgrowth detector for implantable medical device |
US6261280B1 (en) * | 1999-03-22 | 2001-07-17 | Medtronic, Inc | Method of obtaining a measure of blood glucose |
USD424696S (en) * | 1999-05-06 | 2000-05-09 | Therasense, Inc. | Glucose sensor |
USD426638S (en) * | 1999-05-06 | 2000-06-13 | Therasense, Inc. | Glucose sensor buttons |
WO2000076436A1 (en) * | 1999-06-11 | 2000-12-21 | Cochlear Limited | Stimulus output monitor and control circuit for electrical tissue stimulator |
US20030057970A1 (en) * | 2000-04-07 | 2003-03-27 | Yasunori Shiraki | Analyzer and method of testing analyzer |
US6809507B2 (en) * | 2001-10-23 | 2004-10-26 | Medtronic Minimed, Inc. | Implantable sensor electrodes and electronic circuitry |
US7525298B2 (en) * | 2001-10-23 | 2009-04-28 | Medtronic Minimed, Inc. | Implantable sensor electrodes and electronic circuitry |
Also Published As
Publication number | Publication date |
---|---|
US6809507B2 (en) | 2004-10-26 |
JP2005506887A (en) | 2005-03-10 |
EP1446674B1 (en) | 2013-12-25 |
JP4644425B2 (en) | 2011-03-02 |
US20050056539A1 (en) | 2005-03-17 |
EP1446674A1 (en) | 2004-08-18 |
CA2463907A1 (en) | 2003-05-01 |
CA2463907C (en) | 2012-11-20 |
US20030076082A1 (en) | 2003-04-24 |
WO2003036310A1 (en) | 2003-05-01 |
EP1446674A4 (en) | 2005-11-23 |
US7525298B2 (en) | 2009-04-28 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7525298B2 (en) | Implantable sensor electrodes and electronic circuitry | |
US7778679B2 (en) | Implantable sensor and integrity tests therefor | |
EP1030715B1 (en) | Daisy-chainable sensors and stimulators for implantation in living tissue | |
US9060692B2 (en) | Temperature sensor for a leadless cardiac pacemaker | |
CN107874742B (en) | Use of electrochemical impedance spectroscopy in sensor systems, devices, and related methods | |
US6681135B1 (en) | System and method for employing temperature measurements to control the operation of an implantable medical device | |
CA2829673C (en) | Method of and system for stabilization of sensors | |
US11213226B2 (en) | Analyte monitoring devices and methods | |
US8055345B2 (en) | Self-referencing communication in implantable devices | |
US4416282A (en) | Cardiac pacer with improved, output circuitry | |
US5830129A (en) | Process and apparatus for measuring blood flow through an organ or other biological tissue | |
US7611483B2 (en) | Indicator metrics for infection monitoring | |
US4590941A (en) | Cardiac pacer with improved battery system, output circuitry, and emergency operation | |
US4949720A (en) | Apparatus for measuring the lead current in a pacemaker | |
US20080262374A1 (en) | Event triggered infection monitoring | |
US5076271A (en) | Rate-responsive pacing method and system employing minimum blood oxygen saturation as a control parameter and as a physical activity indicator | |
US7766862B2 (en) | Baseline acquisition for infection monitoring | |
US20080262331A1 (en) | Infection monitoring | |
US5218961A (en) | Apparatus for in vivo intracardial of a measured signal corresponding to the physical activity of a subject and a heart pacemaker having a stimulation rate controlled thereby | |
US4437466A (en) | Cardiac pacer with improved battery system, output circuitry, and emergency operation | |
US20070293902A1 (en) | Method of interfacing a sensor lead and a cardiac rhythm management device | |
Chien et al. | Wireless Monitoring of Small Molecules on a Freely-Moving Animal using Electrochemical Aptamer Biosensors | |
Nawito et al. | The SMARTImplant Project |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |