A novel Sensor for Determination of Ascorbic Acid Based on Modified Carbon Paste Electrode

In this study a new method for electrocatalytic oxidation and determination of ascorbic acid (AA) was developed. The proposed electrode was a zeolite-modified carbon paste electrode, which was doped with Ni (II) ions (Ni2+Y/ZMCPE). Ni (II) ions were doped in Y-zeolite framework by ion-exchange mechanism and actd as catalyst to oxidize ascorbic acid. Then, electrocatalytic oxidation of ascorbic acid, using cyclic voltammetry and chronoamperometry techniques was investigated. The diffusion coefficient and current density of ascorbic acid were calculated as 1.491×10-4 cm2 s−1 and 5.17×103 respectively. A linear dynamic range for determination of ascorbic acid and detection limit using proposed modified electrode were  0.02– 4.10 mmolL−1 and 2.8×10−6mol L−1 respectively.