Enzyme-epoxy membrane based glucose analyzing system and medical applications

A semi-automatic glucose analyzing system has been developed. It consists of thin film glucose sensors and a flow injection system with a computerized data processing unit. The sensor is made of titanium and platinum, using the well-established semiconductor process technology. Glucose oxidase is immobilized into the network of epoxy on the electrode surface together with ferrocene, which is used as an electron mediator for reducing the operation voltage of the sensor. The system can measure glucose from 50 to 4000 mg/dl with good linearity up to 400 mg/dl. This can cover the range needed in medical and biotechnological applications. The system can measure samples at a speed of more than 60 samples per hour and has a coefficient of variation of 3%. Selectivity tests were performed and the results showed that there was no interference from sucrose, lactose, maltose, ascorbic acid and uric acid. The sensors were then employed in detecting glucose in human blood plasma samples. The results show good correlation with the results from commercial machines. (C) 1996 Elsevier Science Limited