Liquid-ChromatographicMeasurementof Nitrazepamin Plasma

Inthissimple and rapid“high-performance ” liquid-chro-matographic method for determining nitrazepam in plasma, serum, or whole blood, the sample at pH 7.4 isextracted into diethyl ether with an internal standard (prazepam), chromatographed, and detected at 280 nm with a fixed-wavelength ultraviolet detector. A specimen, together with standardsand a qualitycontrol,can be analyzed in dupli-cate within 90 mm. The limit of sensitivity is 5 j.g/L (ni-trazepam and 7-acetamidonitrazepam) and 50 tg/L (7-aminonitrazepam), and no interferents have been found. This method has the advantages of a small sample re-quirement and complete resolution of nitrazepam and the above-mentioned major metabolites. We have used this method for analysis of therapeutic and overdose con-centrations of nitrazepam, and to investigate the stabilit