An 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)-immobilized electrode for the simultaneous detection of dopamine and uric acid in the presence of ascorbic acid

Abstract

An 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS)-immobilized carbon nanotube (CNT) electrode was used to simultaneously detect dopamine (DA) and uric acid (UA) in the presence of ascorbic acid (AA) with differential pulse voltammetry. When ABTS was immobilized onto the CNT electrode in the presence of DA, UA and 100μM AA, the sensitivity to DA increased from 0.600 (±0.013) to 1.334 (±0.010)μA/μM in the concentration ranges of 0.90–10μM and 1.87–20μM, respectively, and the sensitivity to UA increased from 0.030 (±0.005) to 0.078 (±0.006)μA/μM in the concentration ranges of 2.16–240μM and 3.07–400μM, respectively. These findings demonstrate that the ABTS-immobilized CNT electrode attained a higher sensitivity to UA and also a wider linear range of concentrations.