A Glucose Biosensor Using CMOS Potentiostat and Vertically Aligned Carbon Nanofibers

This paper reports a linear, low power, and compact CMOS based potentiostat for vertically aligned carbon nanofibers (VACNF) based amperometric glucose sensors. The CMOS based potentiostat consists of a single-ended potential control unit, a low noise common gate difference-differential pair transimpedance amplifier and a low power VCO. The potentiostat current measuring unit can detect electrochemical current ranging from 500 nA to 7 μA from the VACNF working electrodes with high degree of linearity. This current corresponds to a range of glucose, which depends on the fiber forest density. The potentiostat consumes 71.7 μW of power from a 1.8 V supply and occupies 0.017 mm
²
of chip area realized in a 0.18 μm standard CMOS process.