Wireless controller for a near infrared multi-channel optical glucose sensor.

摘要

Diabetes is an incurable disease that can affect multiple organs of the human body if left untreated. Ideal treatment of diabetes would involve a closed-loop insulin delivery system or artificial pancreas that is implanted within the patient's body. It would consist of an insulin delivery system with a feedback mechanism so insulin can be delivered in response to the detected changes in the blood glucose concentrations. The key limitation to the successful development of an artificial pancreas is the implantable glucose sensing technology and the electronic support needed to control the instrumentation.; This document describes the design and development of a wireless Controller for an implantable glucose sensor that provides continuous and reagent-free optical analysis of interstitial fluid (ISF). The sensing technology involves sampling of the interstitial fluid in a microfabricated chamber and measurement of the glucose levels based on the absorbance spectrum of the fluid. The Controller provides the necessary electronic support and enables the operation of the sensor for months with minimal user intervention. This new technology will be used as the sensing technology in a feedback controlled insulin delivery system for the in situ treatment of diabetes.; The thesis presents a detailed methodology in designing electronics for a multichannel optical sensor system. A modular design approach is presented where the modules are developed independently and integrated together in the later stages of implementation. The Controller is a wireless microcontroller based electronic circuit custom designed using discrete semiconductor components. Two generations of Controller prototypes have been successfully developed and integrated with sensor prototypes. Sensor characterization has been performed and areas of improvement have been identified. Possible approaches for miniaturization of the electronics have been presented. Microcontroller-based wireless embedded electronics for biomedical sensors provide a promising approach to continuous monitoring of the physiological data at all times. They increase the portability, mobility and extend the reach of the current patient monitoring technology. Equipped with networking capabilities and infrastructure, they provide the medical staff with a better way to offer health care and the patients with an easy mechanism to keep track of their health.