Hydrogenating carbon electrodes by n-butylsilane reduction to achieve an antifouling surface for selective dopamine detection

Abstract

In this work, we have developed an antifouling carbon surface by hydrogenating it using n-butylsilane reduction. After incubating physically small electrodes with such an antifouling carbon surface for 30 min in a synthetic fouling solution containing 1.0 % (v/v) caproic acid (a lipid), 4 % (w/v) bovine serum albumin and 0.01 % (w/v) cytochrome c (both are proteins), and 0.002 % (w/v) human fibrinopeptide B (a peptide), a ∼35 % lower dopamine detection signal was measured. However, no further significant change in dopamine detection signal was observed at electrodes that were incubated in the same synthetic fouling solution for one week, compared to a total loss of detection signal at non-hydrogenated carbon electrodes. We have also demonstrated the unique characteristic of these hydrogenated carbon electrodes in detecting dopamine with minimal interference from as high as 500 μM ascorbic acid that is generally expected in extracellular fluid. Meanwhile, there was also no observable fouling effect at hydrogenated carbon electrodes by the dopamine oxidation product, dopamine-o-quinone (itself a well-known fouling reagent), in the presence of ≤1.0 μM dopamine, which is a 100-fold higher concentration than that in the central nervous system. These results support minimal fouling at n-butylsilane hydrogenated carbon electrodes during dopamine detection in vitro.