Abstract
A rapid, specific and highly sensitive electron-capture gas chromatographic method for the determination of flurazepam and its four metabolites in human urine, serum and plasma was developed. The metabolites in blood specimens and in β-glucuronidase treated urines were cleaned up using porous polymer resin and selective extraction, and were derivatized to trimethyl silylate (TMS), methyl derivatives and methyl ester, respectively. The recoveries were almost quantitative and the sensitivity was enough for therapeutic dose levels (15-30 mg). The sensitivity limits were 0.3-2.0 ng/ml of each metabolites in serum and plasma. The method was applied to urine and serum specimens of single dose of chronic dose of 30 mg of flurazepam, and the metabolic properties of the drug were also discussed.
