Development of a glucose sensor for glucose monitoring in man: The disposable implant concept

Abstract

This paper describes the issues related to glucose sensing in the framework of the concept of disposable implants. The possibility of providing a diabetic patient with a continuous access to his blood glucose concentration and of detecting nocturnal hypoglycaemia would be a major breakthrough in diabetes therapy. To this end, our laboratories have developed a miniaturized, subcutaneous glucose sensor for glucose monitoring. It is based on the enzymatic, amperometric detection of glucose. This glucose sensor has been extensively evaluated in rats, dogs and more recently in human volunteers. Under experimental conditions, a controlled increase in blood glucose concentration is followed by an increase in the current delivered by the sensor. It is then possible to transform this current into an estimation of the glucose concentration. Experiments in rats have shown that the glucose sensor functions for up to 10 days when implanted in the subcutaneous tissue. Experiments in conscious dogs have shown that it works in a subcutaneous tissue closer to the human one. More recently, the glucose sensor was investigated in non-diabetic volunteers. These studies have demonstrated that this subcutaneous glucose sensor is able to provide a reliable estimation of blood glucose concentration in man, making it suitable for blood glucose monitoring. Biocompatibility of the glucose sensor, and particularly long-term tolerance, remains to be demonstrated.