Quantitative analysis of dothiepin HCl by ion selective electrode

Two simple assay procedures for quantitation of dothiepin HCl has been developed using dothiepin-selective electrode. The first (electrode I) was based on drug, falvianic acid ion pair complex, Bis(2-ethylhexyl-phthalate) and poly vinylchroride (PVC) matrix, second electrode (electrode Ⅱ) based on drug, tungstosilicic acid, Bis(2-ethylhexyl sebactate) as plastisizer and polyvinyl chloride matrix. The elctrolodes showed a near-nernsation response in the range of (10^(-2) to 10^(-4)) and (10^(-1) to 10^(-4)) dothiepin over the pH range of 5 to 8 for the two electrods. The selectivity of the electrode to a number of interferences was investigated. This assay was applied to determine dothiepin HCl in capsules and results compared with those obtained by official method.