Gold nanostructures on flexible substrates as electrochemical dopamine sensors

In this study, we fabricated Au nanowires (NWs), nanoslices (NSs), and nanocorals (NCs) on flexible polyethylene terephthalate (PET) substrates via direct current electrochemical depositions. Without any surface modification, the Au nanostructures were used as the electrodes for dopamine (DA) sensing. Among them, the Au NW electrode performed exceptionally well. The determined linear range for DA detection was 0.2-600 μM (N = 3) and the sensitivity was 178 nA/μM cm(2), while the detection limit was 26 nM (S/N = 3). After 10 repeated measurements, 95% of the original anodic current values were maintained for the nanostructured electrodes. Sequential additions of citric acid (CA, 1 mM), uric acid (UA, saturated), and ascorbic acid (AA, 1 μM) did not interfere the amperometric response from the addition of DA (0.1 μM).