System for measuring the efficacy of a sterilization cycle

United States Patent [w]

Bolea

US006063591A [ii] Patent Number: 6,063,591 [45] Date of Patent: *May 16,2000

[58] Field of Search 435/31, 176, 287.4,

435/287.9, 288.1, 288.7; 422/82.08; 436/172

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A system is used for determining efficacy of a sterilization cycle. A biological sterilization indicator exhibits fluorescence in response to biological activity which is indicative of bacterial growth in the biological sterilization indicator. The biological sterilization indicator is exposed to the sterilization cycle and is placed in a fluorescence reading apparatus. The fluorescence from the biological sterilization indicator is read to obtain a first fluorescence reading. The fluorescence from the biological sterilization indicator is re-read to obtain a second fluorescence reading. The efficacy of the sterilization cycle is determined based on the first and second fluorescence readings.

22 Claims, 9 Drawing Sheets