CA2389251A1 - Swelling and deswelling polymer blends - Google Patents

Swelling and deswelling polymer blends Download PDF

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Publication number
CA2389251A1
CA2389251A1 CA002389251A CA2389251A CA2389251A1 CA 2389251 A1 CA2389251 A1 CA 2389251A1 CA 002389251 A CA002389251 A CA 002389251A CA 2389251 A CA2389251 A CA 2389251A CA 2389251 A1 CA2389251 A1 CA 2389251A1
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CA
Canada
Prior art keywords
polymer blend
polymer
drug
chitosan
blend
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.)
Granted
Application number
CA002389251A
Other languages
French (fr)
Other versions
CA2389251C (en
Inventor
Gaylen M. Zentner
Jong-Seok Bark
Feng Liu
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BTG International Ltd
Original Assignee
Individual
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from US09/710,403 external-priority patent/US6537584B1/en
Application filed by Individual filed Critical Individual
Publication of CA2389251A1 publication Critical patent/CA2389251A1/en
Application granted granted Critical
Publication of CA2389251C publication Critical patent/CA2389251C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L1/00—Compositions of cellulose, modified cellulose or cellulose derivatives
    • C08L1/08—Cellulose derivatives
    • C08L1/10—Esters of organic acids, i.e. acylates
    • C08L1/12—Cellulose acetate
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/20—Pills, tablets, discs, rods
    • A61K9/2004—Excipients; Inactive ingredients
    • A61K9/2022—Organic macromolecular compounds
    • A61K9/2031—Organic macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polyethylene glycol, polyethylene oxide, poloxamers
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/20—Pills, tablets, discs, rods
    • A61K9/2004—Excipients; Inactive ingredients
    • A61K9/2022—Organic macromolecular compounds
    • A61K9/205—Polysaccharides, e.g. alginate, gums; Cyclodextrin
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J3/00—Processes of treating or compounding macromolecular substances
    • C08J3/005—Processes for mixing polymers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L5/00—Compositions of polysaccharides or of their derivatives not provided for in groups C08L1/00 or C08L3/00
    • C08L5/02—Dextran; Derivatives thereof
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L5/00—Compositions of polysaccharides or of their derivatives not provided for in groups C08L1/00 or C08L3/00
    • C08L5/08—Chitin; Chondroitin sulfate; Hyaluronic acid; Derivatives thereof
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/20—Pills, tablets, discs, rods
    • A61K9/2004—Excipients; Inactive ingredients
    • A61K9/2022—Organic macromolecular compounds
    • A61K9/2027—Organic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polyvinyl pyrrolidone, poly(meth)acrylates
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/20—Pills, tablets, discs, rods
    • A61K9/2004—Excipients; Inactive ingredients
    • A61K9/2022—Organic macromolecular compounds
    • A61K9/205—Polysaccharides, e.g. alginate, gums; Cyclodextrin
    • A61K9/2054—Cellulose; Cellulose derivatives, e.g. hydroxypropyl methylcellulose

Abstract

A polymer blend is prepared by dissolving chitosan and a second polymer in an acidic aqueous solution to form an aqueous polymer blend, dehydrating said aqueous polymer blend, and recovering said polymer blend. The second polymer may be selected from the group consisting of polyether glycols including polyethylene glycols; cellulose esters including cellulose acetate;
poloxamers; polysaccharides including dextran and guar; polyvinylpyrrolidones;
polyvinyl alcohols; and mixtures or copolymers thereof. These polymer blends swell in an acidic environment and deswell in a more neutral or basic environment. This technology is valuable for the dispensing of biologically active material or drugs into a surrounding environment, especially the environment as is found in the gastrointestinal tract. Since the various polymer blends of the present invention are not covalently or ionically crosslinked, but are physically combined, each polymer in the physical blend maintains its original chemical structure, and therefore, is safe for oral or other routes of administration.

Claims (22)

1. A polymer blend that swells in an acidic environment and deswells in a more neutral or basic environment comprising chitosan and a second polymer wherein said chitosan and second polymer are not covalently or ionically crosslinked, and wherein said polymer blend is prepared by dissolving chitosan and a second polymer in an acidic aqueous solution to form an acidic aqueous polymer blend solution, dehydrating said acidic aqueous polymer blend solution, and recovering therefrom said polymer blend.
2. A polymer blend as in claim 1 wherein said chitosan to said second polymer weight ratio is from about 1:4 to 10:1.
3. A polymer blend as in claim 2 wherein said second polymer is selected from the group consisting of polyether glycols, cellulose esters, poloxamers, polysaccharides, polyvinylpyrrolidones, polyvinyl alcohols, and mixtures or copolymers thereof.
4. A polymer blend as in claims 1 to 3 wherein said chitosan is from 50% to 95% deacetylated and has a Brookfield viscosity from about 100 to 10000 cps.
5. A polymer blend as in claims 1 to 3 wherein the acid in said acidic aqueous solution is a member selected from the group consisting of acetic acid, citric acid, hydrochloric acid, and combinations thereof.
6. A polymer blend as in claim 5 wherein the concentration of said acid in said acidic aqueous solution is from about 0.5 M to 11 M.
7. A polymer blend as in claim 6 wherein said acid is acetic acid.
8. A polymer blend as in claim 7 wherein said second polymer is selected from the group consisting of polyether glycols, poloxamers, polysaccharides, polyvinylpyrrolidones, polyvinyl alcohols, and mixtures or copolymers thereof, and wherein said acetic acid concentration is from about 1 M to 2 M.
9. A polymer blend as in claim 7 wherein said second polymer is a cellulose ester, and wherein said acetic acid concentration is from about 8 M to 11 M.
10. A polymer blend as in claim 4 wherein said chitosan has a Brookfield viscosity from about 440 cps to 3,640 cps.
11. A polymer blend as in claims 1 to 3 wherein said second polymer has a weight average molecular weight (Mw) from about 1,000 to 4,000,000.
12. A polymer blend as in claims 1 to 3 wherein pH controlling additives or excipients are admixed with said polymer blend to alter the swelling and deswelling properties of said polymer blend.
13. A polymer blend drug composition that, when exposed to aqueous conditions, swells in an acidic environment and deswells in a more neutral or basic environment comprising an effective amount of a drug combined with a polymer blend, said polymer blend comprising chitosan and a second polymer, wherein said chitosan and said second polymer are not covalently or ionically crosslinked.
14. A polymer blend drug composition as in claim 13 wherein said polymer blend is prepared by dissolving said chitosan and said second polymer in an acidic aqueous solution to form an aqueous polymer blend, dehydrating said aqueous polymer blend, and recovering said polymer blend.
15. A polymer blend drug composition as in claim 14 wherein said chitosan to said second polymer weight ratio is from about 1:4 to 10:1.
16. A polymer blend drug composition as in claims 13 to 15 wherein said second polymer is selected from the group consisting of polyether glycols, cellulose esters, poloxamers, polysaccharides, polyvinylpyrrolidones, polyvinyl alcohols, and mixtures or copolymers thereof.
17. A polymer blend drug composition as in claims 13 to 15 wherein said chitosan is from 50% to 95% deacetylated and has a Brookfield viscosity from about 100 cps to 10,000 cps.
18. A polymer blend drug composition as in claim 13 wherein said drug is combined with said chitosan and said second polymer by dissolving said drug, said chitosan, and said second polymer in the acidic aqueous solution to form a drug containing aqueous polymer blend, and dehydrating said drug containing aqueous polymer blend to form a particulate drug containing polymer blend, and grinding said particulate drug containing polymer blend.
19. A polymer blend drug composition as in claim 13 wherein said drug is combined with said chitosan and said second polymer by swelling said polymer blend in an acidic solution containing said drug, equilibrating said swollen polymer blend and said drug, and dehydrating said swollen polymer blend containing said drug.
20. A polymer blend drug composition as in claim 13 wherein said drug is combined with said chitosan and said second polymer by admixing said drug in a particulate form with said polymer blend in a particulate form.
21. A polymer blend drug composition as in claim 17 wherein said chitosan has a Brookfield viscosity from about 440 cps to 3460 cps.
22. A polymer blend drug composition as in claim 17 wherein said second polymer has a weight average molecular weight (Mw) from 1,000 to 4,000,000.
CA2389251A 1999-11-12 2000-11-10 Swelling and deswelling polymer blends Expired - Fee Related CA2389251C (en)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
US43888499A 1999-11-12 1999-11-12
US09/438,884 1999-11-12
US09/710,403 US6537584B1 (en) 1999-11-12 2000-11-09 Polymer blends that swell in an acidic environment and deswell in a basic environment
US09/710,403 2000-11-09
PCT/US2000/030908 WO2001034677A1 (en) 1999-11-12 2000-11-10 Swelling and deswelling polymer blends

Publications (2)

Publication Number Publication Date
CA2389251A1 true CA2389251A1 (en) 2001-05-17
CA2389251C CA2389251C (en) 2010-03-23

Family

ID=27031834

Family Applications (1)

Application Number Title Priority Date Filing Date
CA2389251A Expired - Fee Related CA2389251C (en) 1999-11-12 2000-11-10 Swelling and deswelling polymer blends

Country Status (12)

Country Link
US (2) US7182957B2 (en)
EP (1) EP1240230B1 (en)
CN (1) CN1181816C (en)
AT (1) ATE318846T1 (en)
AU (1) AU775527B2 (en)
BR (1) BR0015521B1 (en)
CA (1) CA2389251C (en)
DE (1) DE60026357T2 (en)
ES (1) ES2259618T3 (en)
HK (1) HK1052713B (en)
MX (1) MXPA02004583A (en)
WO (1) WO2001034677A1 (en)

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US8789536B2 (en) 2007-10-17 2014-07-29 The Invention Science Fund I, Llc Medical or veterinary digestive tract utilization systems and methods
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US8109920B2 (en) * 2007-10-31 2012-02-07 The Invention Science Fund I, Llc Medical or veterinary digestive tract utilization systems and methods
US8808271B2 (en) * 2007-10-31 2014-08-19 The Invention Science Fund I, Llc Medical or veterinary digestive tract utilization systems and methods
US8333754B2 (en) * 2007-10-31 2012-12-18 The Invention Science Fund I, Llc Medical or veterinary digestive tract utilization systems and methods
US20090163894A1 (en) * 2007-10-31 2009-06-25 Searete Llc, A Limited Liability Corporation Of The State Of Delaware Medical or veterinary digestive tract utilization systems and methods
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Also Published As

Publication number Publication date
EP1240230A1 (en) 2002-09-18
US7182957B2 (en) 2007-02-27
US20030139495A1 (en) 2003-07-24
CA2389251C (en) 2010-03-23
CN1181816C (en) 2004-12-29
US6730327B2 (en) 2004-05-04
ES2259618T3 (en) 2006-10-16
BR0015521A (en) 2002-11-19
DE60026357T2 (en) 2006-10-19
EP1240230A4 (en) 2004-12-01
DE60026357D1 (en) 2006-04-27
WO2001034677A1 (en) 2001-05-17
AU1760501A (en) 2001-06-06
HK1052713B (en) 2005-08-19
HK1052713A1 (en) 2003-09-26
CN1399655A (en) 2003-02-26
WO2001034677A8 (en) 2001-10-11
ATE318846T1 (en) 2006-03-15
AU775527B2 (en) 2004-08-05
EP1240230B1 (en) 2006-03-01
US20030124189A1 (en) 2003-07-03
MXPA02004583A (en) 2002-09-02
BR0015521B1 (en) 2013-04-02

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