GAS-LIQUID CHROMATOGRAPHY OF SUBMICROGRAM AMOUNTS OF DRUGS .4. IDENTIFICATION OF BARBITURATES HYDANTOINS AMIDES IMIDES CARBAMATES PHENYLBUTAZONE CARBOXYLIC ACIDS AND HYDRAZINE DERIVATIVES BY DIRECT DERIVATIVE FORMATION WITHIN GAS CHROMATOGRAPH

By the single injection of a mixture of N,O-bistrimethylsilylacetamide and drug into the gas chromatograph, trimethylsilyl derivatives of carboxylic acids, barbiturates, amides, imides, hydantoins, carbamates, phenylbutazone, hydrazine derivatives, alcohols, phenols and certain amines can be formed within the apparatus. The retention time (tr) of the derivative may be less than, equal to, or greater than the tr of the parent drug; peak shapes are more symmetrical; sensitivity is increased. These factors, together with information obtained by a similar procedure of derivative formation (where applicable) using aldehydes, ketones and acid anhydrides, provide additional parameters for use in drug identification both in simple solution and in extracts of biological material. © 1969.