Determination of amitriptyline and cocaine by GC and GC/MS in biological fluids.

A method of identification and quantitative determination of amitriptyline and cocaine at trace levels in biological fluids is described. After the extraction of both drugs from the biological material in an alkaline medium, and posterior purification and concentration of the extract, one proceeds to unequivocal identification using the combined capillary GC/MS system with the Selected Ion Monitoring (SIM) technique. Quantitative determination is carried out by GC with a N-P detector. The precision of the method and limits of sensitivity are presented.