SOLID-PHASE EXTRACTION AND GC MS CONFIRMATION OF BARBITURATES FROM HUMAN URINE

A highly selective and sensitive procedure has been developed for isolating and identifying barbiturates In human urine. With a new disposable bonded silica gel solid-phase extraction (SPE) column and hexobarbital as an internal standard (IS), amobarbital, butabarbital, pentobarbital, phenobarbital, secobarbital, and methaqualone were selectively isolated from endogenous urine components. Capillary gas chromatography/Ion trap mass spectrometry (GC/MS) analysis of the extracts generated a full mass spectrum for the detection, identification, and quantitation of barbiturates. Linear quantitative response curves for the drugs have been generated over a concentration range of 20-500 ng/mL. Overall extraction efficlencles for drugs averaged greater than 90%, and the quantitative response curves exhibited correlation coefficients of 0.996 to 0.999. © 1992, Oxford University Press. All rights reserved.