A sensitive thin-layer chromatography technique for determining morphine in urine

Abstract A screening procedure is described for determining morphine and other narcotics in acid-hydrolyzed urine. A simple pH adjustment and extraction are followed by washing the extracting solvent with a phosphate buffer which effectively removes hydrolytic products that normally produce inferior chromatograms. Interfering substances are discussed, with special reference to methadone, nicotine, caffeine, and phenothiazine compounds.