Sensor for Continuous Monitoring of Glucose Level

Period of Performance: 09/30/1998 - 03/31/2000


Phase 2 SBIR

Recipient Firm

Therasense, Inc.
Alameda, CA 94502
Principal Investigator


TheraSense Inc. will bring to market a system, based on a redundant pair of glucose electrodes, self-implanted by the patient, providing continuous information of the blood glucose concentration and alarms for actual and impending hypo/hyperglycemia. The active area of the implanted electrodes is 5x1O(-4) cm(2) and their 10-90% rise/decay time is <150 sec., a time short enough to provide not only the concentration in time for adjustment through insulin administration or food intake but also the first and second derivatives needed both for predicting impending hypo/hyperglycemia and for correcting for transiently large differences between subcutaneous and blood glucose concentrations when the rate of change in either is fast. The implanted electrodes are calibrated by independent analysis of a single sample of blood ("one point in-vivo calibration"). They do not consume oxygen and have no leachable constituents. They are based on electrical connection ("wiring") of reaction centers of glucose oxidase to miniature gold dots. The amount of material in the transduction layer, electron-conducting glucose-permeable hydrogel, comprising glucose-oxidase and its "wire", is 1 microgram. PROPOSED COMMERCIAL APPLICATIONS: The worldwide market for glucose meters and disposables was estimated at $2 billion in 1996 and is growing at a 15% annual rate. Over 8 million Americans have been diagnosed with diabetes. Diabetes is the fourth leading cause of death by disease (1600,000 cases/year), the leading cause of blindness in adults (15,000-39,000), the leading cause of renal failure (<13,000) and the leading cause of amputations (54,000). The total cost in the US of treating diabetics is estimated at $105 billion in 1992 (including $60 billion for hospitalizations) or $1 of every $7 spent on acute care.