Automated solid-phase extraction and two-step derivatisation for simultaneous analysis of basic illicit drugs in serum by GC/MS

Abstract

A combination of automated solid-phase extraction (SPE) and subsequent two-step derivatisation has been developed for the simultaneous analysis of basic drugs of abuse and cocaine metabolites in serum samples. Substances included in this procedure are morphine, codeine, methadone, cocaine, benzoylecgonine, methylecgonine, amphetamine, methamphetamine, MDMA, MDEA and MDA. SPE with mixed-mode cartridges (RP-C8 and cation-exchange) was fully automated with a Zymark RapidTrace SPE robot. GC/MS analysis was performed after derivatisation with a new two-step reaction by trifluoroacetic anhydride and 2,2,3,3,3-pentafluoropropanol. High recoveries (> 85%) with high reproducibility (CV 1.1-3.8%) were found for all drugs. High correlation coefficients (r > 0.998) were obtained due to the addition of deuterated standards prior to extraction. Experience obtained over 2 years of applying this method to drug analysis in serum is discussed.

Validated semiquantitative/quantitative screening of 51 drugs in whole blood as silylated derivatives by gas chromatography-selected ion monitoring mass spectrometry and gas chromatography electron capture detection

“…Further improvements in reliability can be achieved by hyphenated chromatographic techniques, i.e. gas chromatography-mass spectrometry (GC-MS) [11][12][13][14][15], and liquid chromatography-mass spectrometry (LC-MS) [16][17][18]. The former is still preferred in toxicological analyses owing to its better sensitivity with several compounds, lower cost of analysis and manifold acquisition costs of LC-MS system.…”

Simple and rapid analysis of four amphetamines in human whole blood and urine using liquid–liquid extraction without evaporation/derivatization and gas chromatography–mass spectrometry

“…The sensitivity of this method was equal to or slightly lower than that of the methods described in the literature using LLE or SPE with evaporation [19,27], and lower than the method involving derivatization [10], although it met the requirements for confirmation testing of recreational drugs. As mentioned above, in clinical and forensic toxicology laboratories, confirmation of the presence of recreational drugs using mass spectrometry is conducted only for positive cases from initial immunoassay screening, which requires that the confirmation method is at least as sensitive as the screening test.…”

“…The sample preparation for several samples Forensic Toxicol could be completed in less than 10 min, including 5 min for centrifugation. It was much quicker than the methods using LLE [10,20] or SPE [26,27] with evaporation, especially with low evaporation temperature. In this study, the addition of acid was not needed, and no extra timeconsuming derivatization steps were involved, which proved to be much simpler than many other methods [20,23,28].…”

Separation of positional CPP isomers by chiral HPLC-DAD of seized tablets

“…Because in four different countries only m-CPP is a controlled substance and not o-and p-CPP, there is demand for an analytical confirmation method that can detect o-, m-, p-CPP isomers. Several analytical methods have been described for the identification of various amphetamines and analogues including m-CPP, among them GC and CE separations combined with mass-selective and UV detection [14,[16][17][18][19][20][21]. To this day, only one method has been described for distinguishing between the three positional isomers of CPP by chiral CE-ESI-MSMS [14].…”