Electrochemical studies of ganciclovir at glassy carbon electrodes and its direct determination in serum and pharmaceutics by square wave and differential pulse voltammetry

Abstract

A simple and rapid electrochemical method for the determination of ganciclovir in human serum and pharmaceutics was developed. The anodic peak at +1.15 V obtained in a buffer on glassy carbon electrode was used for analysis. The peak current and peak potential depends on pH, scan rate and initial potential. Decrease of the anodic peak with increasing pH, as well as deviations from linear plots of i p = f( C) and i p = k v 1 / 2 indicate that this peak at higher concentrations is affected by adsorption–desorption phenomena. At concentrations lower than about 1 × 10 −4 M the peak current obtained by differential pulse and square wave voltammetry is practically a linear function of concentration and is suitable for quantitative determination in pharmaceutical dosage forms and human serum. The linear response was obtained in the ranges of 1 × 10 −6–1 × 10 −4 M give detection limit on one decimal point: 8.1 × 10 −8 M for DPV and 4.52 × 10 −8 M for SWV techniques. The similarly repeatability of the methods was within 1.40–1.05% for peak currents and 0.19–0.11% for peak potentials for DPV and SWV, respectively. Precision and accuracy of the developed method was checked by recovery studies.