Detection of cocaine and cocaethylene in sweat by solid-phase microextraction and gas chromatography/mass spectrometry.
In the present work, a semi-quantitative method was developed to detect simultaneously cocaine (COC) and cocaethylene (CE) (transesterification product of the coingestion of COC with ethanol) in sweat. Sweat samples were collected by means of a non-occlusive sweat patch device supplied by PharmChek. The method was based on the dissolution of COC and CE incorporated into the patch, with 0.2 M sodium acetate buffer (pH 5.0) and the extraction of the analytes by solid-phase microextraction (SPME). Gas chromatography/mass spectrometry (GC-MS) was used to detect the analytes in selected ion monitoring mode (SIM). The method showed to be very simple, rapid and sensitive. The limits of detection were 5 ng/ml for COC and CE (12.5 ng/patch). Good inter and intra-assay precision was also observed (coefficient of variation <8%) with the use of deuterated internal standards.
College of Pharmaceutical Sciences, Toxicology, University of S. Paulo, USP, Av. Professor Lineu Prestes, 580 B13B CEP 05508-900 São Paulo, SP, Brazil.
Maria José Damas
MJ
Follador
Mauricio
M
Yonamine
Regina Lucia
RL
de Moraes Moreau
Ovandir Alves
OA
Silva
D003042:Cocaine / Q000031:analogs & derivatives* / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013542:Sweat / Q000737:chemistry*
C066444:cocaethylene; D003042:Cocaine