Determination of desmethyldiazepam in plasma by electron-capture GLC: application to pharmacokinetic studies of clorazepate.
Plasma desmethyldiazepam concentrations were quantitated by a rapid and sensitive technique using electron-capture GLC. Following addition of diazepam as the internal standard, plasma is extracted at physiological pH into benzene-isoamyl alcohol. The extract is evaporated to dryness and reconstituted with toluene-isoamyl alcohol prior to chromatography. Both diazepam and desmethyldiazepam are quantitatively extracted. The variation of identical samples is 5%, and the sensitivity is 5 ng of desmethyldiazepam/ml of original sample. The method is applicable to pharmacokinetic studies of clorazepate, a benzodiazepine derivative transformed to desmethyldiazepam prior to absorption.
D014151:Anti-Anxiety Agents / Q000378:metabolism*; D002849:Chromatography, Gas / Q000379:methods; D003009:Clorazepate Dipotassium / Q000378:metabolism*; D003975:Diazepam / Q000031:analogs & derivatives*; D005260:Female; D006801:Humans; D007700:Kinetics; D003708:Nordazepam / Q000097:blood*; D013997:Time Factors
D014151:Anti-Anxiety Agents; D003009:Clorazepate Dipotassium; D003708:Nordazepam; D003975:Diazepam