Differential pulse polarographic determination of clorazepate monopotassium and dipotassium

Polarographic investigation of clorazepate monopotassium and dipotassium showed two cathodic waves at about -1.28 and -1.66 v. The cathodic wave associated with clorazepate monopotassium or dipotassium at about -1.66 v was a pH-independent, diffusion-controlled wave. This wave was used to develop a specific stability-indicating procedure for clorazepate monopotassium and dipotassium in the presence of their degradation products, namely, nordiazepam, 2-amino-5-chlorobenzophenone, and glycine. The method involves a 10(-2) M LiOH-10(-1) M LiCl extraction of the active ingredient from the formulation, filtration, dilution with the same supporting electrolyte, and then use of the standard addition technique for drug quantitation in capsules. Typical fomulation excipients did not interfere with the analysis. Accuracy and precision of the procedure were 99.55 +/- 0.68%.