Multiplexing neurochemical detection with carbon fiber multielectrode arrays using fast-scan cyclic voltammetry

Abstract

Carbon fiber microelectrodes (CFMEs) have been extensively used to measure neurotransmitters with fast-scan cyclic voltammetry (FSCV) due to their ability to adsorb cationic monoamine neurotransmitters. Although FSCV, in tandem with CFMEs, provides high temporal and spatial resolution, only single-channel potentiostats and electrodes have been primarily utilized. More recently, the need and use of carbon fiber multielectrode arrays has risen to target multiple brain regions. Previous studies have shown the ability to detect dopamine using multielectrode arrays; however, they are not readily available to the scientific community. In this work, we interfaced a carbon fiber multielectrode array (MEA or multielectrode array), to a commercially available four-channel potentiostat for multiplexing neurochemical measurements. The MEA's relative performance was compared to single CFMEs where dopamine detection was found to be adsorption controlled to the electrode's surface. Multiple waveforms were applied to each fiber of the multielectrode array simultaneously to detect different analytes on each electrode of the array. A proof of concept ex vivo experiment showed that the multielectrode array could record redox activity in different areas within the mouse caudate putamen and detect dopamine in a 3-mm 2 area. To our knowledge, this is the first use of the multielectrode array paired with a commercially available multichannel potentiostat for multi-waveform application and neurotransmitter co-detection. This novel array may aid in future studies to better understand complex brain heterogeneity, the dynamic neurochemical environment, and how disease states or drugs affect separate brain areas concurrently.

Semiconducting electrodes for neural interfacing: a review

“…However, more recent works have demonstrated the feasibility of multiplexing to enable a single FSCV to be used for multiple electrodes. 284 Beyond this, the triangular waveform with a fast sweep of voltage over time is expected to be generated for a range of rates. This requires a relatively high-speed clock that works with a counter and a reasonably high-resolution digital-to-analogue converter (DAC).…”

Roadmap on nanomedicine for the central nervous system

“…Apart from pharmacological treatments, the monitoring of DA levels in vivo and in real time is necessary to understand its physiological roles. In this sense, different sensors and biosensors have been developed, as those based in measuring neurotransmitters with fast-scan cyclic voltammetry (FSCV) using multielectrode arrays [92]. These studies help to better understand the complex brain heterogeneity, the dynamic neurochemical environment, and how disease states or drugs affect separate brain areas concurrently.…”

Letting the little light of mind shine: Advances and future directions in neurochemical detection

“…To determine the relationship between local electrical activity and changes in neurochemical concentrations, probes for simultaneous FSCV and electrophysiological recording have been developed (Hobbs et al, 2017;Owesson-White et al, 2016). Advances in voltammogram analysis, alternate waveform development (other than the traditional triangle waveform, discussion below), and specialized probes have allowed for simultaneous, multiplexed detection of different neurochemicals (Hersey et al, 2021;Rafi and Zestos, 2021a;Wang and Venton, 2017).…”