Differential pulse voltammetric determination of chlorphenoxamine hydrochloride and its pharmaceutical preparations using platinum and glassy carbon electrodes

Voltammetric methods have been used for the determination of chlorphenoxamine hydrochloride (Ch-HCl) in raw material and in its pharmaceutical preparations (Allergex and Allergex caffeine tablet). It was found that Ch-HCl gives a characteristic cyclic voltammetric (CV) and differential pulse voltammetric (DPV) peak in acetonitrile using platinum and glassy carbon working electrodes. The I (p) of the DPV peak increases linearly within the concentration range from 4.5 x 10(-4) to 1.0 x 10(-2) mol L-1 of the investigated drug. The concentration of Ch-HCl in raw drug material and in its pharmaceutical preparations was determined using the standard addition method, Randles-Sevcik equation and indirectly via its complexation with sodium tetraphenylborate (NaTPB). The obtained over all average recoveries were 101.44 and 100.49% with SD 0.45 and 0.38 (n = 4) for platinum and glassy carbon electrodes, respectively. The effect of scan rate, sample concentration, and supporting electrolyte on the I (p) and E (p) was also investigated.