Fabrication of TiO2 Nanoparticles Carbon Paste Electrode Bulk-Modified with Novel Hydroquinone for Determination of Ascorbic Acid

A sensitive and selective electrochemical method for the determination of ascorbic acid (AA) was developed using a modified TiO2 nanoparticles carbon paste electrode. Cyclic voltammetry was used to investigate the redox properties of this modified electrode at various solution pH values and at various scan rates. This modified carbon paste electrode shows excellent electrocatalytic activity toward the oxidation of AA in a phosphate buffer solution (pH 8.0). The linear range of 0.3 to 20.0 mu M and a detection limit of 1.43 x 10(-7) M were observed in pH 8.0 phosphate buffer solution. Also, the modified electrode was employed for the determination of AA in the real samples such as AA ampoule using standard addition method.