A point of care electrochemical impedance spectroscopy device

Abstract

Electrochemical Impedance Spectroscopy (EIS) is a label-free method of molecular detection of particular interest for biomedical applications. We aim to create a hand-held, easy to use EIS measurement device, for biomolecular detection. Electrochemical cyclic voltammetry systems help millions of diabetics monitor their blood glucose levels 2-8 times per day, but their use is very limited due to the poor lower limit of detection. The EIS technique can be used to detect a much larger array of biomolecules at very low concentration. Our EIS system generates the magnitude and phase of the impedance from test samples via MATLAB, which provides the real and imaginary components of the impedance. The circuit was integrated on a single chip and fabricated in a standard 0.5 μm CMOS technology. A hand-held EIS measurement system was built using the chip and an Arduino Uno to measure a Randles circuit equivalent over the frequency range from 1 Hz to 2 kHz, the measurement and simulation results show excellent agreement.