HPLC method for simultaneous determination of clobazam and N-desmethylclobazam in human serum, rat serum and rat brain homogenates.

A method for simultaneous determination of clobazam (CBZ) and its active metabolite N-desmethylclobazam (DCBZ) in various biological samples by RP-HPLC with UV detection is described. The determination of both CBZ and DCBZ is performed without derivatization. The internal standard is diazepam. The method is rapid and simple with sensitivity limits of 10 ng/mL for both CBZ and DCBZ and is suitable for routine analysis as well as for animal studies.