Determination of salicylic acid in pharmaceutical formulations and foods by differential-pulse voltammetry using a glassy carbon electrode

Abstract

A simple and rapid voltammetric method for the determination of salicylic acid in pharmaceutical preparations and foods has been developed. The sample was extracted using either diethyl ether or ethanol-diethyl ether and then back-extracted into 0.015 M disodium hydrogen phosphate solution. The peak current was measured using a glassy carbon electrode at 0.85 V. The working range was 0–25 p.p.m. The average recovery for ointment was 99% with a standard deviation of 5.0%. Results are reported for eight different pharmaceutical formulations.