Analysis of ascorbic acid by electrochemical detection

Abstract

A glassy carbon electrode (GCE) modified by copper-doped titanium dioxide nanoneedles has been fabricated and used for the electrochemical detection of ascorbic acid (AA) in KCl solution. Two pairs of peak currents on quasi-reversible electrochemical cyclic voltammogram peaks (cvps) are located at +0.16 V,–0.03 V (cvp 1 and cvp 2) and +0.01 V,–0.44 V (cvp 1′ and cvp 2′), respectively. The relationship between the peak current and AA concentration is linear in the concentration range from 0.0005 to 2 mM. There is also a linear relationship between the peak current and the scan rate. The detection limit is 0.37 μM and 0.25 μM for cvp 1 and cvp 2, respectively, at a signal-to-noise ratio of 3. A GCE modified by copper-doped titanium dioxide nanoneedles exhibts good stability and has promising characteristics for the detection of AA.