Simultaneous determination of dextropropoxyphene, norpropoxyphene and methaqualone in plasma by gas chromatography with selective nitrogen detection.

A method for the identification and quantification of dextropropoxyphene, norpropoxyphene, and methaqualone in plasma by GC/NPD is presented. The procedure employs cyclizine as the internal standard and requires no derivatization. After a single-step extraction, analysis is achieved in 8 min. The lower limits of detection were found to be 6, 12, and 1 ng/ml for dextropropoxyphene, norpropoxyphene, and methaqualone, respectively. This method appears to be rapid, sensitive, and applicable to forensic and clinical toxicological analyses.