title: Confirmation and quantitation of cocaine, benzoylecgonine, ecgonine methyl ester, and cocaethylene by gas chromatography/mass spectrometry. Use of microwave irradiation for rapid preparation of trimethylsilyl and T-butyldimethylsilyl derivatives.
abstract: The authors developed a technique by which cocaine metabolites as well as cocaethylene can be identified and quantitated using gas chromatography/mass spectrometry (GC/MS), and deuterated standards of benzoylecgonine, cocaine, ecgonine methyl ester, and cocaethylene as internal standards. The authors used a solid phase extraction (Clean Screen, Worldwide Monitoring Corporation, (Horsham, PA)) technique, and rapid derivatization of metabolites using microwave irradiation before GC/MS analysis. The t-butyldimethylsilyl derivatives (prepared by microwave irradiation in 2.5 minutes, 640 Watts [W]) offered better baseline separation and chromatography than conventional trimethylsilyl derivatives. The assay was linear between 0.87-17.3 mumol/L of benzoylecgonine (250-5,000 ng/mL) concentration, 0.83-16.6 mumol/L of cocaine (250-5,000 ng/mL), 0.79-15.8 mumol/L of cocaethylene (250-5,000 ng/mL) and 1.25-25.1 mumol/L of ecgonine methyl ester (250-5,000 ng/mL). The yields are comparable between the microwave technique and conventional heating.
authors.affiliation: Department of Pathology, University of New Mexico School of Medicine, Albuquerque, USA.
authors.forename: W C
authors.initials: WC
authors.lastname: Thompson
authors.forename: A
authors.initials: A
authors.lastname: Dasgupta
mesh_terms: D003042:Cocaine / Q000031:analogs & derivatives / Q000032:analysis* / Q000378:metabolism* / Q000528:radiation effects; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D008872:Microwaves; D014297:Trimethylsilyl Compounds / Q000378:metabolism / Q000528:radiation effects
chemical_list: D014297:Trimethylsilyl Compounds; C005618:benzoylecgonine; C066444:cocaethylene; D003042:Cocaine; C034524:ecgonine methyl ester