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
μM and a detection limit of 1.43 × 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.
