Through the electrical """"""""wiring"""""""" of glucose oxidase the basis has been formed for subcutaneously implantable, miniature (O.29mm OD) flexible glucose sensors that have no leachable components; are insensitive to variation of partial pressure of oxygen; are insensitive to interferants; operate at 37degreesC for one week with only 4% variation in sensitivity; are not fouled by cell growth; are calibrated, for the first time, in vivo by the long- sought one-point calibration. When the glucose concentration was monitored with pairs of the microwire sensors in rats and the sensors were calibrated at any one point, 99% of the glucose readings were clinically correct. The novel microsensors that are innocuous and comfortable to wear in the abdominal skin, will be developed for enhanced compliance of Type I diabetics with the recommendations of the 1993 Diabetes Control and Compliance Trial (DCCT, 1993). Issues relating to the design and use of reliable innocuous microsensor pairs, weekly replaced by the diabetic, will be answered. Specifically the feasibility of designing electron conducting, enzyme wiring hydrogels to provide sufficient specificity for glucose, for one-point in vivo calibration; the feasibility of further miniaturization, while the reliability, stability and operational life are improved; the feasibility of achieving >99% clinical accuracy through implanting pairs of microsensors and accepting only those readings that pass the probability ratio test applied in nuclear reactors monitored with sensor pairs; and the feasibility of developing algorithms for translating the measured subcutaneous time-concentration profiles to the clinically relevant blood glucose concentrations will be addressed.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK042015-06
Application #
2331425
Study Section
Special Emphasis Panel (ZRG7-SSS-8 (06))
Program Officer
Harmon, Joan T
Project Start
1992-02-01
Project End
1999-01-31
Budget Start
1997-02-01
Budget End
1998-01-31
Support Year
6
Fiscal Year
1997
Total Cost
Indirect Cost
Name
University of Texas Austin
Department
Engineering (All Types)
Type
Schools of Engineering
DUNS #
City
Austin
State
TX
Country
United States
Zip Code
78712
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