Screening, identification, and quantitation of benzodiazepines in postmortem samples by HPLC with photodiode array detection

A high-performance liquid chromatographic method has been developed for the simultaneous analysis of eight frequently used benzodiazepines and some of their metabolites in postmortem samples. The method includes a liquid-liquid extraction with n-hexane-ethyl acetate (70:30, v/v), gradient elution of a C8 reversed-phase column with an alkaline water-methanol eluent free of buffer salts, and photodiode array detection. This allows rapid detection, a purity check, identification, and quantitation of the eluting peaks. Recovery and linearity data are good for the chosen parent compounds. The validated procedure has been applied routinely in forensic toxicological analyses. The elimination of the buffer from the eluent results in a robust procedure, free of technical problems and long rinsing periods.