Simultaneous determination of benzodiazepines by ultraviolet--visible spectrophotometry in micellar media

A method for the simultaneous determination of benzodiazepines in binary mixtures is proposed, based on the acid hydrolysis of benzodiazepines to benzophenones and the spectrophotometric determination of the latter in the presence of Nemol K 1030, a non-ionic surfactant condensate of ethylene oxide with nonylphenol. The experimental conditions for the hydrolysis of several benzodiazepines in sealed Pyrex tubes were determined. The addition of Nemol K 1030 to acidic solutions of benzophenones modified the positions of the absorption bands and made possible the simultaneous analysis of binary mixtures of benzodiazepines.