Determination of cocaine and cocaethylene in urine by solid-phase microextraction and gas chromatography-mass spectrometry.
In order to evaluate recent cocaine exposure or its coingestion with ethanol, a simple and sensitive solid-phase microextraction (SPME) procedure for determination of cocaine and cocaethylene in urine was developed and validated. A polydimethylsiloxane fibre (100 microm) was submersed in the urine sample for 20 min under magnetic stirring after alkalinization with solid buffer (NaHCO(3):K(2)CO(3), 2:1). Gas chromatography-mass spectrometry (GC-MS) was used to identify and quantify the analytes in selected ion monitoring mode (SIM). The limits of quantification were 5.0 ng/mL for both analytes. Good inter- and intra-assay precision was also observed (coefficient of variation <9%).
Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, Av. Professor Lineu Prestes, 580 B13B, CEP 05508-900, São Paulo, SP, Brazil. yonamine@usp.br
Mauricio
M
Yonamine
Alessandro Morais
AM
Saviano
D003042:Cocaine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000652:urine*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D015394:Molecular Structure; D015203:Reproducibility of Results
C066444:cocaethylene; D003042:Cocaine