Square wave voltammetric determination of ascorbic acid in food and pharmaceutical samples using a novel room temperature ionic liquid ZnO nanoparticles carbon paste electrode

In this paper we report synthesis and application of zno nanoparticle (zno/nps) and 1, 3-dipropylimidazolium bromide as high sensitive sensors for voltammetric determination of ascorbic acid (aa) using carbon paste electrode. the zno/nps was characterized with different methods such as tem and xrd. the cyclic voltammogram showed an irreversible oxidation peak at 0.35 v (vs. ag/agclsat), which corresponded to the oxidation of aa. compared to common carbon paste electrode, the electrochemical response was greatly improved. the electro-oxidation of aa occurred in a ph-dependent 2e? and 2h+ process, and the electrode reaction followed a diffusion-controlled pathway. under the optimum conditions, the voltammetric oxidation peak current of aa showed two linear dynamic ranges with a detection limit of 0.04 ?m for aa. the novel sensor has been found selective and successfully implemented for the determination of aa in fresh vegetable juice; fruit juices, tablet and tablet samples without previous preparation and were compared with a published electrochemical method.