Dopamine detection at antifouling conical-tip carbon electrodes

A significant achievement in this work is the development of antifouling conical-tip carbon electrodes (similar to 2.7 mu m tip diameter and similar to 165 mu m axial length) suitable for detection of the neurotransmitter dopamine in-vivo. These electrodes were hydrogenated using a diphenylsilane reduction method to yield a hydrophobic surface to deter adsorption of amphiphilic biomolecules. Initially, hydrogenated carbon electrodes were electrochemically characterised using several redox markers. The degree of antifouling was then assessed by the voltammetric signal change of dopamine at these electrodes before and after being incubated in a fouling solution containing bovine serum albumin, cytochrome C (both are proteins) and caproic acid (a lipid). In our work, we have obtained only a 6.9% (standard deviation 3.5%, N = 40) decrease in dopamine signals at the hydro-genated carbon electrodes. These results strongly support the diphenylsilane reduction strategy for the development of antifouling biosensors for dopamine detection in biological matrices.