RT Journal Article SR Electronic T1 THE USE OF THIN-LAYER CHROMATOGRAPHY FOR THE ANALYSIS OF DRUGS. ISOLATION AND IDENTIFICATION OF BARBITURATES AND NONBARBITURATE HYPNOTICS FROM URINE, BLOOD AND TISSUES JF Journal of Pharmacology and Experimental Therapeutics JO J Pharmacol Exp Ther FD American Society for Pharmacology and Experimental Therapeutics SP 154 OP 159 VO 139 IS 2 A1 Cochin, Joseph A1 Daly, John W. YR 1963 UL http://jpet.aspetjournals.org/content/139/2/154.abstract AB An adaptation of thin-layer chromatography for the isolation and identification of a number of the commercially available barbiturates and nonbarbiturate hypnotics is described. The method is rapid, inexpensive and simple. The hypnotics are extracted directly from urine, blood or tissue homogenate, without prior precipitation of proteins, into methylene chloride at pH 5.0. After evaporation of the extracting solvent, the drugs are taken up in a small volume of ethanol and spotted on thin-layer chromatoplates. Rf values for 16 barbiturates and 4 non-barbiturate hypnotics in three solvent systems are given. Some examples of the metabolism of several of the barbiturates and nonbarbiturate hypnotics after their administration to humans are described in order to show the usefulness of thin-layer chromatography in metabolic studies as well as in the fields of toxicology and forensic medicine. In the course of these studies of the practical applicability of these techniques, a metabolite of secobarbital, 5-allyl-5-(1-hydroxy-1-methylbutyl) barbituric acid, was isolated. This compound had been previously isolated from dog urine after administration of secobarbital, but had not been isolated from human urine.