On-site biosignal amplification using a single high-spin conjugated polymer

Abstract

Abstract On-site or in-sensor biosignal transduction and amplification can offer several benefits such as improved signal quality, reduced redundant data transmission, and enhanced system integration1,2. A promising candidate for this purpose is ambipolar organic electrochemical transistors (OECTs) due to their favorable attributes, including high transconductance, low operation voltage, biocompatibility, and suitability for miniaturized amplifier design3,4. However, the performance of ambipolar OECT materials has remained limited, hindering their successful application in on-site biosignal amplification. Here, we propose to use high-spin, hydrophilic conjugated polymers and a computational screening approach to address this challenge. We designed a high-spin polymer, namely P(TII-2FT), which exhibits balanced and exceptionally high ambipolar OECT performance. The figure-of-merits achieved by the P(TII-2FT) devices surpass those of the current leading materials by 5 to 20 times, resulting in a remarkable voltage gain exceeding 800 V/V while maintaining a compact form factor. Based on the amplifier, we have successfully achieved on-site capture and amplification of various electrophysiological signals with greatly enhanced signal quality.