Electrochemical Behavior and the Detection Limit of Ascorbic Acid on a Pt Modified Electrode

The electrochemical behavior of ascorbic acid (AA) at the DL-Alanine (DL-Ala) polymer film modified platinum electrode (DL-Ala/Pt electrode) had been studied by using cyclic voltammetry. The main proposition of the research is also to indicate the detection limit of AA on the used modified electrode. The modified electrode shows an excellent electrocatalytical effect on oxidation of AA in 0.1 M KH2PO4 using cyclic voltammetry. The effect of DL-Ala/Pt modified electrode increases clear by the anodic current peak about 13.67 μA while the peak potential shifts to negative values as compared to the bare Pt electrode. The anodic current increased with an increase in AA concentration from 2 mM to 7.5 mM and with increasing scan rate from 20-200 mV/s and it is potential shifted to more positive values. The detection limit of this modified electrode with AA was calculated to be 9.24x10-6 M. Chronoamperometric measurements were used to find the diffusion coefficient of AA with a value of 6.92 x 10–6 cm2s-1.