A rapid procedure for the screening and quantitation of barbiturates, diazepam, desmethyldiazepam and methaqualone

A procedure is presented for the concomitant identification and quantitation of certain commonly abused weak acid and natural drugs from whole blood. This procedure offers several advantages over other procedures in that: (A) a means of extraction of the drugs from blood using a very inexpensive source of diatomaceous earth (Celite 560) is presented, (B) the addition of three internal standards allows the quantitation of several drugs from blood with just one extraction of the blood sample, (C) the extracts are virtually free of any contaminants from biological sources or from biologically inert drug metabolites, and (D) the barbiturates and desmethyldiazepam are derivatized to enhance their limits of detection and reduce peak tailing frequently observed when using the nitrogen-phosphorous detector and gas chromatography (NPD/GC). Some 1000 positive driving-under-the-influence cases have been quantitated by this method.