Routine identification of drugs of abuse in human urine : I. Application of fluorometry, thin-layer and gas—liquid chromatography

Abstract

The methods described in this report were developed for the rapid analysis of over 500 urines per day for psychoactive drugs. These techniques involve extraction of the drugs from biological material, scanning the extract by automated spectro-fluorometry, extensive use of thin-layer chromatography coupled with sequential chromogenic spraying and application of gas—liquid chromatography as an adjunct method for positive identification and confirmation. The urinalysis laboratory requires a 50–60 ml sample from which a 2 ml aliquot is subjected to fluorometric analysis. The positive morphine and/or quinine samples were then acid hydrolyzed, extracted at pH 9 and the extracts applied to thin-layer plates and the presence of morphine and quinine confirmed by R F values and reactions with specific chromogenic spray reagents. A 15 ml aliquot of the urine was extracted at pH < 1 for barbiturates, diphenylhydantoin and glutethimide. The extract was applied to chromagram sheets developed and sprayed with reagents that provide reactions with these acidic drugs. A 25 ml aliquot of the urine was extracted at pH 10–11 for opiates, opioids, amphetamines, phenothiazines and tranquilizers. The organic extract was divided into A and B fractions, and these fractions developed on separate thin-layer silica gel plates. The A fraction was sprayed with chromogenic reagents primarily to detect amphetamine and analogues. The B fraction was sprayed with reagents to detect opiates, opioids, tranquilizers and phenothiazines. However, the reactions and R F values on the A and B plates were usually cross compared for the various drugs of abuse. The methods and techniques were relatively simple to perform and the psychoactive drugs could be detected in the range of 1 to 5 μg/ml of urine.