Solid-phase microextraction for the determination of cocaine and cocaethylene in human hair by gas chromatography-mass spectrometry.
A method for the simultaneous determination of cocaine (COC) and cocaethylene (CE) in human hair was developed, using solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) as analytical technique to identify and quantify the drugs. Selected ion monitoring (SIM) mode was used to obtain higher sensitivity. The deuterated-labeled analogues were used as internal standards. The detector response was linear for the drugs studied over the range 0.4-15 ng/mg, with correlation coefficients higher than 0.995. The coefficients of variation oscillated between 0.65% and 14.18% and the accuracy was in the range from 0.73% to 11.20%. The limits of quantitation and detection were found to be acceptable. Finally, this method was applied to 15 hair samples from cocaine users, obtaining positive results in all cases. The mean concentrations were 5.39 ng/mg (range: 0.43-8.98 ng/mg) for cocaine and 1.11 ng/mg (range: 0.42-2.23 ng/mg) for cocaethylene.
Bermejo
Ana María
AM
Institute of Legal Medicine, Forensic Toxicology Service, Faculty of Medicine, San Francisco, s/n, 15782 Santiago de Compostela, Spain. apimlana@usc.es
López
Patricia
P
Alvarez
Iván
I
Tabernero
María Jesús
MJ
Fernández
Purificación
P
D000328:Adult; D003042:Cocaine / Q000031:analogs & derivatives* / Q000032:analysis*; D018765:Dopamine Uptake Inhibitors / Q000032:analysis*; D005260:Female; D005554:Forensic Medicine / Q000379:methods; D008401:Gas Chromatography-Mass Spectrometry; D006197:Hair / Q000737:chemistry*; D006801:Humans; D008297:Male; D015203:Reproducibility of Results
D018765:Dopamine Uptake Inhibitors; C066444:cocaethylene; D003042:Cocaine