Dopamine and ascorbate analysis at hydrodynamic electrodes of boron doped diamond and nitrogen incorporated tetrahedral amorphous carbon

摘要

Rotating and hydrodynamically modulated rotating disk electrodes of boron-doped diamond (BDD) and tetrahedral amorphous nitrogen incorporated carbon (taC: N) were employed to extend analytical sensitivity and linear current response of these materials for dopamine analysis at physiological pH to 200 nM. Hydrodynamically modulated rotating disk electrode (HMRDE) techniques discriminate against nonmass transfer limited components, allowing more complete implementation of the wider electrochemical window of these materials. Experiments performed in the presence of ascorbate showed typical catalytic enhancement of the dopamine oxidation current and a corresponding loss of response to dopamine quinone at the ring in a rotating ring-disk electrode (RRDE) configuration. Utilizing these phenomena, a RRDE method for simultaneous determination of both dopamine and ascorbate concentrations in solutions containing comparable levels of both species is presented. [References: 38]