title: Analysis of cocaine and benzoylecgonine in urine by using multisyringe flow injection analysis-gas chromatography-mass spectrometry system.
abstract: In this paper, a method was described to determine cocaine (COC) and benzoylecgonine (BZE) in human urine samples by GC-MS detection. The extraction of analytes from urine samples was achieved in an Oasis hydrophilic-lipophilic balance column (20 mmx3.9 mm id, dp=25 microm; Waters, USA), incorporated in a multisyringe flow injection system, used for the sample treatment. Finally, to improve the volatility of the BZE, an in-line derivatization reaction with N,O-bis (trimethylsilyl) trifluoroacetamide with 1% trimethylchlorosilane was made microwave-assisted in order to reduce the reaction time. The results showed that the proposed method is a good alternative for the analysis of COC and BZE in urine samples because it offers advantages compared with those described in the literature, which include simplicity in the sample treatment, the sensitivity and selectivity necessary to determine the analytes of interest at low levels in the urine and high sample throughput.
authors.affiliation: Laboratorio de Espectroscopia Molecular Departamento de Química, Facultad de Ciencias, Universidad de Los Andes, Mérida, Venezuela. brunetto@ula.ve
authors.forename: María del Rosario
authors.initials: Mdel R
authors.lastname: Brunetto
authors.forename: Yelitza
authors.initials: Y
authors.lastname: Delgado
authors.forename: Sabrina
authors.initials: S
authors.lastname: Clavijo
authors.forename: Yaritza
authors.initials: Y
authors.lastname: Contreras
authors.forename: Dina
authors.initials: D
authors.lastname: Torres
authors.forename: Carlos
authors.initials: C
authors.lastname: Ayala
authors.forename: Máximo
authors.initials: M
authors.lastname: Gallignani
authors.forename: Rafael
authors.initials: R
authors.lastname: Forteza
authors.forename: Víctor
authors.initials: V
authors.lastname: Cerdà Martin
mesh_terms: D003042:Cocaine / Q000031:analogs & derivatives* / Q000652:urine*; D017022:Flow Injection Analysis / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D057230:Limit of Detection; D008872:Microwaves; D052616:Solid Phase Extraction
chemical_list: C005618:benzoylecgonine; D003042:Cocaine