Bioavailability of Clonazepam in human plasma using a simple HPLC

We aimed at determining bioavailability of clonazepam, an anxiolytic drug, and developing a simple analysis in human blood using HPLC. A rapid and sensitive HPLC method was developed and validated using reverse-phase C18 column with retension time and limit of quantification of clonazepam being 2.58 min and 5hg/ml, respectively. Quantification was performed at 235 nm with p-hydroxybenzoic acid ethyl ester as internal standard. The method involved a simple extraction. In order to study blood level profile in time, sight volunteers were enrolled and orally took 6 mg clonazepam once. (omitted)