Design of a multi-channel high-sensitivity electrochemical interface IC based on organic electrochemical transistors (OECT)

This paper proposes an interface IC that implements a Current Convey and Resistor (CC+R) based potentiostat architecture for the detection of a maximum 2mA DC current with an I
rms
of 50nA. The relative reference bias design based on the OECT source reduces the relative voltage instability caused by switching between channels. The programmable output stage based on the adjustable gain amplifier (PGA) and 13-bit Successive Approximation Register Analog-to-digital converter (SAR ADC) achieves a dynamic range of more than 80dB. The detection of the Tumor Necrosis Factor-alpha (TNF-α) based on this interface IC achieves the highest 10fMol sensitivity.