A telemetry-instrumentation system for monitoring multiple subcutaneously implanted glucose sensors

Abstract

An implantable potentiostat-radiotelemetry system for in vivo sensing of glucose is described. An enzyme electrode sensor measures the oxidation current of hydrogen peroxide formed by the stoichiometric conversion of glucose substrate and oxygen cofactor in an immobilized glucose oxidase layer. The sensor current is converted to a frequency and transmitted at programmable intervals (4, 32, 256 s) to a remote receiver. Low power CMOS circuitry is employed and device operation for up to 1.5 years is predicted using two series connected 250 mAh lithium cells. Crystal controlled RF frequencies uniquely identify each sensor allowing over 10 sensors within the same 10 m radius. A custom interface card allows a PC to program the receiver and handle the transmitted sensor data using software written in Microsoft C and QuickBasic. Software control allows on-the-fly sensor addition or subtraction to the sensor group being monitored. Over 10 sensors can be tracked long-term using the longest transmit interval, or four sensors can be tracked during short-term infusion studies when the transmit interval is reduced to 4 s. The design, construction, operation, and performance of the system hardware and software are described and evaluated.

Wireless Body Area Network: An Overview and Various Applications

“…Implantable biosensors are an important class of biosensors based on their ability to continuously measure metabolite levels, without the need for person interference and regardless of the person's physiological state (sleep, rest, etc.) [5]. the implantable biosensors have great impact to diabetes and trauma care patients, as well as soldiers in action (military).…”

Carbon Nanomaterials: Applications in Physico-chemical Systemsand Biosystems

“…The CNT electromechanical actuators (known as artificial muscles) generates higher stresses than natural muscles and higher strains than high-modulus ferroelectrics. The MWCNTs are excellent candidates for electromechanical devices because of large surface area as well as their high electrical conductivity 109,110 .…”

Carbon Nanotubes for Biomedical Applications

“…Therefore, because of their small size and less power consumption, they are highly suitable as implantable sensors. Implanted sensors can be used for monitoring pulse, temperature and blood glucose, and diagnosing diseases [192], [194]. Besides, CNTs can be used for repairing damaged cells or killing them by targeting tumors by chemical reactions.…”