ABSTRACT
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.
Subject(s)
Chromatography, Gas/methods , Clonazepam/blood , Benzodiazepines/blood , Chromatography, Gas/instrumentation , Clinical Trials as Topic , Evaluation Studies as Topic , Humans , Reproducibility of ResultsABSTRACT
A method has been developed for gas-chromatographic determination of clobazam in human plasma using a nitrogen-selective detector. The unchanged drug was extracted from the plasma at pH 9 by benzene. The method used methyl-1-clonazepam as internal standard. Calibration graphs were linear in the range of 20 to 10,000 ng/ml. The recovery of the compound was 102.29%. The sensitivity of the method was adequate for determination of the drug at toxic concentrations and at therapeutic doses. It was a simple, rapid, reproductible method for determination of clobazam and most of the commercialized benzodiazepines. The method has been tested in a few number of clinicals cases. No interferences occurred in plasma from patients treated with various drugs.