Stripping voltammetric determination of valsartan in bulk and pharmaceutical products.

ABSTRACT

Stripping voltammetric determination of valsartan using a hanging mercury drop electrode (HMDE) was described. The method was based on adsorptive accumulation of the species at HMDE, followed by first harmonic alternating current AC stripping sweep at pH 6. The behavior of adsorptive stripping response was thoroughly studied under various experimental conditions, e.g. type of supporting electrolyte, pH, accumulation time, scan rate and mode of sweep. In Britton-Robinson buffer solution, a quasi-reversible reduction process involving transfer two electrons and two protons was took place. The response was linear over the concentration range of 0.08-0.64 microg/ml with regression coefficient 0.999 and limit of detection 0.02 microg/ml. The average of determinations of the cited compound in oral dosages with its standard deviation was 101.11 +/- 4.38%. The result obtained by the proposed method was compared with that obtained by the UV-spectrophotometric technique. Furthermore, the proposed method was successfully applied as stability-indicating method for determining valsartan in the presence of its acid induced degradation products.