Quantitative analysis of temazepam in plasma by capillary gas chromatography: Application to pharmacokinetic studies in rats

A sensitive method was developed for the determination of temazepam in plasma using capillary gas chromatography. After the extraction into dichloromethane-pentane (1∶1), temazepam was quantitated as its O-trimethylsilyl derivative on a capillary column with a63Ni electron capture detector using prazepam as internal standard. The detector response was found to be linear in the concentration range 0.031 to 8 μg mL−1. The detection limit was about 3.5 ng mL−1. The intraday and inter-day coefficients of variation were below 9%. The method was used to determine the pharmacokinetic profile of temazepam in rats after intravenous administration.