Determination of cutting agents in seized cocaine samples using GC-MS, GC-TMS and LC-MS/MS

Cocaine is usually sold as a white powder and can contain several adulterants and diluents, known as cutting agents. The cutting agents play an important role in the identification of trafficking routes, and they can also modify or intensify signs and symptoms of drug intoxication increasing the risk to the health's user. The purpose of this work was to quantify cocaine and cutting agents in 116 illicit samples from NMS Labs, Willow Grove, PA, U.S. Gas chromatography - mass spectrometry (GC-MS) and handle-portable gas chromatography toroidal ion trap mass spectrometry (GC-TMS) were used as screening methods A liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantification of cocaine, levamisole, benzocaine, phenacetin, hydroxyzine, theophylline, diltiazem, acetaminophen and caffeine. Cocaine-d3 and caffeine-d3 were used as internal standards. The method was shown to be precise, accurate and linear over a range of 50-2000ng/mL for all analytes. Cocaine was the only detected compound in 16.37% (n=19) of the samples. Between the identified cutting agents, levamisole was the most abundant substance found (79.31% of the total samples, amounts ranging from 0.2 to 74.3%), followed by phenacetin (18.96%, 0.3-46.8%), caffeine (12.06%, 0.2-32.2%), hydroxyzine (9.48%, 0.7-13.8%) and benzocaine (5.17%, 0.4-58.3%). GC-TMS was considered suitable to be used as a tool in forensic analysis as a screening method for cocaine, benzocaine, phenacetin, hydroxyzine and caffeine with restrictions to be used for levamisole, while GC-MS presented good results in screening analysis for cocaine, levamisole, benzocaine, phenacetin, hydroxyzine and caffeine.