[Extraction of glutethimide and methyprylon from blood using thin layer chromatography]

Glutethimide and methyprylone were extracted from blood and plasma at pH ca. 4 (acetate buffer) thrice with chloroform, using 2.5 solvent volume ratio to that of aqueous phase. Phenobarbital was used as an internal standard in thin-layer chromatography experiments on silica gel--to obtain of comparable ratios of Rf values of glutethimide and/or methyprylone to that of phenobarbital. Suitable conditions of the separation of three substances were established using one of following mobile phases: benzene-dioxane-aq.ammonia (15:4:1), chloroform-acetone-aq.ammonia (25:25:1), chloroform-acetone-diaethylamine (5:4:1) and chloroform-diethyl ether-acetone (5:3:2); on 7.5 x 2.5 cm plates; development time (at 5 cm distance) was up to 10 minutes. The concentrations as small as 0.1 microg of examined substances in 1 cm3 of plasma may be identified on chromatograms using 20% Na2CO3 solution.