A portable point-of-use EIS device for in-vivo biomédical applications

In this paper, a compact system for point-of-use EIS (Electrochemical Impedance Spectroscopy) experiences is described. This is based on a custom electronic instrumentation, post processing software and low-cost disposable three-electrodes sensor. The designed electronic is based on a signal generator, a potentiostat and a digital lock-in amplifier supported by a real time platform, which allows the instrumentation control and real time data processing. Moreover the device is connected to a remote computer for a user-friendly device management and easy data display. The studies presented consist on complete EIS experiences in order to get a full system characterization in terms of magnitude and phase using passive components and ferrocyanide/ferricyanide solution, a commonly used substance on sensor and equipment characterization. As a result, we were able to detect impedance with an average error of less than 3% and a SNR rejection of-40 dB in a frequency working range of 10 Hz to 100 kHz.