Subminiature implantable potentiostat and modified commercial telemetry device for remote glucose monitoring

A subminiature implantable potentiostat and telemetry electronics package was developed to provide remote monitoring of implantable amperometric glucose sensors. Included are a new potentiostat for sensor biasing, a transimpedance amplifier to produce the sensor-current proportional voltage, and an optically coupled interface to the commercially available telemetry unit which transmits glucose concentration data to a corresponding receiver and computer. Potentiostat components were individually tested in vitro for accuracy and stability, and as a system utilizing telemetry for end-to-end remote data monitoring. In vitro calibrations of a glucose sensor obtained with our subminiature potentiostat/telemetry unit and a traditional potentiostat correlated extremely well (R2 = 0.9994). Instrumentation developed in this paper will allow other researchers to easily develop implantable units for their own applications.