Rapid High-Performance Liquid Chromatographic Method for the Measurement of Temazepam in Blood-Plasma or Serum

Summary

A simple high-performance liquid chromatographic method has been developed for the measurement of temazepam in small (200 μl) volumes of plasma or serum. After addition of 0.02 mol/1 Tris buffer, pH 7.4 (50 μl) containing an internal standard, the sample is vortex mixed with diisopropyl ether (200 μl) for 30 sec. and centrifuged at 9950.g for 3 min. A portion (100 μl) of the resulting extract is analysed on a microparticulate (5 μ) silica column using methanol:diethyl ether (75:25) containing perchloric acid (0.025% v/v) as the mobile phase, and the absorption of the column effluent is monitored at 240 nm. No endogenous sources of interference have been observed. The limit of sensitivity of the assay is 0.02 mg/1, and the method is applicable to the simultaneous assay of some other benzodiazepines.