Fabrication and Optimization of a Molecularly Imprinted Carbon Fiber Microelectrode for Selective Detection of Met-enkephalin Using Fast-Scan Cyclic Voltammetry

Abstract

Methionine-enkephalin (Met-Enk) is an endogenous opioid peptide that is involved in various physiological processes including memory. A technological gap in the understanding of Met-Enk's role in memory is the lack of rapid measurement tools to selectively quantify Met-Enk concentrations in situ. Here, we integrate molecularly imprinted polymers (MIPs) with carbon fiber microelectrodes (CFMs) to selectively detect Met-Enk by using fast-scan cyclic voltammetry (FSCV). We report two MIP conditions that yield 2-fold and 5-fold higher selectivity toward Met-Enk than the tyrosine-containing hexapeptide fragment angiotensin II (3−8). We demonstrate that MIP technology can be combined with FSCV at CFMs to create rapid and selective sensors for Met-Enk. This technology is a promising platform for creating selective sensors for other peptides and biomarkers.

Waveform Optimization for the In Vitro Detection of Caffeic Acid by Fast-Scan Cyclic Voltammetry

“…After dynamic range testing, stability testing was performed, in a manner consistent with other reports, ,, with the results shown in Figure . Panel 5A shows peak currents, normalized to the first injection, for 32 consecutive FIA measurements of 750 nM caffeic acid, recorded over the course of approximately 1.5 h. There was no significant difference in peak current across the 32 injections (ANOVA P = 0.165, N = 5), and the average relative standard deviation in peak currents across all electrodes was 0.96%.…”