Application of fast gas chromatography/mass spectrometry for the rapid screening of synthetic anabolic steroids and other drugs in anti-doping analysis.
ABSTRACT This paper describes a fast gas chromatographic/mass spectrometric (GC/MS) screening method for the detection, in urine, of 36 xenobiotics (30 synthetic anabolic steroids, four narcotics, one diuretic and one stimulant) excreted free or as glucuro-conjugates in urine and detectable as trimethylsilyl (TMS) derivatives. These drugs (and/or their urinary metabolites) can be simultaneously extracted by a single liquid/liquid separation step, at alkaline pH, after enzymatic hydrolysis with beta-glucuronidase and then assayed as TMS derivatives by GC/MS using electron ionisation (EI) and single ion monitoring (SIM) acquisition mode. The total time needed for the GC run is less than 8 min. Good reproducibility of the retention times (CV% <1) and the relative abundances of the diagnostic fragment ions (CV% <10) was observed for all target analytes. The sensitivity of the method is sufficient to match the requirements of the World Anti-Doping Agency (WADA) for the accredited laboratories, with limits of detection (LODs) that are lower than the corresponding WADA minimum required performance limits (MRPLs) for all target compounds.
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ABSTRACT: There is revived interest in the development and implementation of methods of faster GC. The paper summarises the advantages of faster GC analysis, general approaches to faster GC method development and practical aspects of fast gas chromatography with the utilisation of open tubular capillary columns with the stress on trace analysis. There are a number of ways to take the advantage of the improved speed of analysis by faster GC. Numerous options exist for pushing the speed of capillary gas chromatography (CGC) analysis. The scope of this paper is also to give an overview of the present state of faster GC instrumentation which is already available for trace analysis. The practicality of fast CGC is a function of sample preparation and the matrix interferences and how they affect the resultant resolution that may be achieved. Researchers have demonstrated the applicability of fast GC to trace and ultratrace analysis of volatile and semivolatile compounds also with narrow bore columns and difficult sample matrices (such as food, and soil extract). The main development of faster GC methods has been observed in the field of environmental analysis. Practical applications are presented. Both optimised sample preparation and experimental conditions for faster GC are the future perspective of trace analysis.Journal of Chromatography 07/2003; 1000(1-2):199-221. · 4.61 Impact Factor
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ABSTRACT: An analytical procedure was developed for the simultaneous sensitive identification, screening and quantitation of 30 drugs of abuse using 250 microl of human oral fluid. The method employs sequential mixed-mode solid-phase extraction (SPE), optimized derivative formation and long-column fast gas chromatography/electron impact mass spectrometry (GC/EI-MS). After sequential SPE elution, the most sensitive and stable derivatives were formed by taking careful account of the characteristics of the active functional groups and possible steric hindrances affecting derivatization chemistry. Amphetamine-type stimulant drugs were acylated with heptafluorobutyric anhydride, benzodiazepines and Delta(9)-tetrahydrocannabinol were silylated with N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide and benzoylecgonine, codeine, ethylmorphine, 6-monoacetylmorphine, morphine, pholcodine, buprenorphine and norbuprenorphine with N-methyl-N-(trimethylsilyl)trifluoroacetamide. In addition, the following analytes were included: methadone, cocaine, alprazolam, midazolam, fentanyl and zolpidem. In GC separation, fast temperature ramping and high carrier gas flow-rate combined with long 30 m columns of i.d. 0.32 mm offered a reduction in analysis time and sharp peak shapes while still maintaining sufficient resolution and high sample capacity. Validated parameters including selectivity, linearity, accuracy, intra- and inter-day precision, extraction efficiency and limit of quantitation were all within required limits. In contrast to previously published methods, this single procedure is suitable for the simultaneous toxicological determination of the most common illicit drugs and benzodiazepines, and also zolpidem, in a small amount of oral fluid.Journal of Mass Spectrometry 07/2005; 40(6):739-53. · 3.21 Impact Factor