[Determination of unchanged clonazepam in plasma by gas-liquid chromatography]

A gas-liquid chromatography method for unchanged clonazepam determination in plasma using a nitrogen-phosphorus detector is presented. The drug is extracted from buffered plasma at pH 9.0 with benzen. The proposed method is simple, rapid and permits to determine clonazepam with a good precision (delta = 3.10 p. cent) and reproductibility (CV = 3.04 p. cent). The method allows the determination of other benzodiazepins. Plasmatics levels of inchanged clonazepam had been determined on some clinical cases.