Compact Electrochromic Optical Recording of Bioelectric Potentials

Kenneth Nakasone; Chris Zavik; Erica Liu; Burhan Ahmed; Dana Griffith; Lothar Maisenbacher; Ashwin Singh; Yuecheng Zhou; Bianxiao Cui; Holger Müller

arXiv · 2311.15506

Compact Electrochromic Optical Recording of Bioelectric Potentials

Kenneth Nakasone·Chris Zavik·Erica Liu·Burhan Ahmed·Dana Griffith·Lothar Maisenbacher·Ashwin Singh·Yuecheng Zhou·Bianxiao Cui·Holger Müller

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Abstract

Electrochromic optical recording (ECORE) is a label-free method that utilizes electrochromism to optically detect electrical signals in biological cells with a high signal-to-noise ratio and is suitable for long-term recording. However, ECORE usually requires a large and intricate optical setup, making it relatively difficult to transport and to study specimens on a large scale. Here, we present a compact ECORE apparatus that drastically reduces the spatial footprint and complexity of the ECORE setup whilst maintaining high sensitivity. An autobalancing differential photodetector automates common-mode noise rejection, removing the need for manually adjustable optics, and a compact laser module conserves space compared to a typical laser mount. The result is a simple, easy-to-use, and relatively low cost system that achieves a sensitivity of 16.7 μV (within a factor of 5 of the shot noise limit), and reliably detects action potentials from Human-induced pluripotent stem cell (HiPSC) derived cardiomyocytes. This setup can be further improved to within 1.5 dB of the shot noise limit by filtering out power-line interference.

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Kenneth Nakasone, Chris Zavik, Erica Liu, Burhan Ahmed, Dana Griffith, Lothar Maisenbacher, Ashwin Singh, Yuecheng Zhou, Bianxiao Cui, Holger Müller. 2023-11-27. Compact Electrochromic Optical Recording of Bioelectric Potentials. https://arxiv.org/abs/2311.15506

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