Fast-Scan Cyclic Voltammetry (FSCV) at carbon-fiber microelectrodes is an electrochemical technique used to detect electroactive neurotransmitters in the brain. The conventional FSCV platform for calibrating electrodes uses a 6-port, 2-way actuator flow injection analysis (FIA) system. The conventional FIA platform has a few disadvantages including an unwanted mechanical switching noise, large volumes of expensive analytes, and requires making multiple calibration solutions by hand, introducing potential human error. Here, we developed an alternative approach to electrode calibration involving a microfluidic flow cell system. One previous report of a FSCV flow cell system on-chip exists; however, the dimensions of the device were still macroscale which required larger sample volumes. Here, we used SU-8 photolithography with PDMS soft lithography. The device consists of two PDMS layers: the bottom layer includes a Y-channel at the top, 100 µm tall, 400 µm wide and 33 mm long, with a T-channel at the end for waste removal, and a top layer which contains the tubing inlets and a 2-mm-well aligned over the T-channel end for electrode placement. The well is large enough to include a Ag/AgCl reference electrode. The flow rates used for both Y-inlets did not exceed 1 µL/min in total flow rate to facilitate full diffusion within the channel. With this design, full calibration curves can be generated on-chip with a single analyte concentration with buffer due to mixing within the channel. The dimensions of the device combined with on-line mixing allows for significantly reduced sample volume from several mL to less than 50 µL. This phenomenon was verified both by mixing colors on-chip and comparing to hand-made color mixing using Image J and by modeling using COMSOL Multiphysics software. Overall, we present a new microfluidic flow cell which facilitates rapid calibration curve generation, with low sample volume, and limited cost.

Fast-scan cyclic voltammetry flow cell on-chip

Macromolecular Chemistry: The Second Century

[Author Benefits](https://scimeetings.acs.org/?utm_source=pubs_content_marketing&utm_medium=website&utm_campaign=0320_MCF_NPI_Launch_Spring_Homepage&ref=pubs_content_marketing)

[How to use SciMeetings](https://storage.googleapis.com/dl.morressier.com/acs/SciMeetings-ACSSpring2020-HowToGuide_M3020-Final.pdf)

[Frequently Asked Questions](https://storage.googleapis.com/dl.morressier.com/acs/SciMtng_ACSNMSp2020_FAQ_M3120_Final.pdf)

ACS Spring 2020 National Meeting & Expo

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.