Analysis of trace amounts of barbiturates in saliva

A simple gas chromatographic method is presented for the determination of trace quantities (0.1-1.0 microgram/ml) of amobarbital, pentobarbital and phenobarbital in saliva. The barbiturate is extracted with chloroform, alkylated with bis(2-chloroethyl) sulphate, and quantified using a non-polar (SE-30) column and electron-capture detection. The procedure has been applied to the determination of the salivary half-lives of amobarbital and, for the first time, pentobarbital following administration of the drugs to human volunteers. The scale and sensitivity of detection are suitable for use in forensic or other medico-legal work.