Dual-Color Optical Recording of Bioelectric Potentials by Polymer Electrochromism

Abstract

Optical recording based on voltage-sensitive fluorescent reporters allows for spatial flexibility of measuring from desired cells, but photobleaching and phototoxicity of the fluorescent labels often limit their sensitivity and recording duration. Voltage-dependent optical absorption, rather than fluorescence, of electrochromic materials, would overcome these limitations to achieve long-term optical recording of bioelectrical signals. Electrochromic materials such as PEDOT:PSS possess the property that an applied voltage can either increase or decrease the light absorption depending on the wavelength. In this work, we harness this anticorrelated light absorption at two different wavelengths to significantly improve the signal detection. With dual-color detection, electrical activity from cells produces signals of opposite polarity, while artifacts, mechanical motions, and technical noises are uncorrelated or positively correlated. Using this technique, we are able to optically record cardiac action potentials with a high signal-to-noise ratio, 10 kHz sampling rate, >15 min recording duration, and no time-dependent degradation of the signal. Furthermore, we can reliably perform multiple recording sessions from the same culture for over 25 days.

Nanotechnology and Cancer Bioelectricity: Bridging the Gap Between Biology and Translational Medicine

“…On the other hand, from an engineering perspective, the scientific community working in cellular electrical recording mainly targeted the development of cutting-edge technological advancements to record action potentials in excitable cells. [126][127][128][129][130][131] This field of research is highly active and in constant expansion from the nanotechnology side. Microelectrode arrays record extracellular signals in excitable cells using highly precise plug-andplay systems operating at high resolutions.…”

Electrical and Optical Modulation of a PEDOT:PSS‐Based Electrochemical Transistor for Multiple Neurotransmitter‐Mediated Artificial Synapses

“…Indeed, optical detection approaches have emerged in the last years due to their unprecedented flexibility for choosing regions of interest. [23,24] This work paves the way for sophisticated bio-hybrid neuromorphic interfaces, comprising array of mutually dependent devices that are controlled by multiple neurotransmitters resulting from a variety of physiological cues that can be closely monitored using noninvasive optical readouts.…”

“…Indeed, optical detection approaches have emerged in the last years due to their unprecedented flexibility for choosing regions of interest. [ 23,24 ]…”

Soluble polymer facilely self-grown in situ on conducting substrates at room temperature towards electrochromic applications

“…[9][10][11] Currently, there are several methods to fabricate films, including spin-coating, spray-coating, bladecoating, and electrochemical polymerization, which were derived during the progress of the development of the electrochromic field. [12][13][14][15] However, the application of spin-coating and spray-coating methods requires specialized instruments, such as a spin coater or spray gun. Thus, the quality of the film depends on the experience of the preparers.…”