Resumen de Validation of a method to detect cocaine and benzoylecgonine in human whole blood by gas chromatography-mass spectrometry and application in body packers and stuffers cases in the north of chile

Felipe Bravo, Maria Cecilia Contzen, Julio Mollo, Pedro Buc Calderon, Julio Benites

• The present paper describes a method for the simultaneous determination of cocaine and benzoylecgonine in human whole blood. The drugs were extracted with phosphate buffer at pH 6, followed by solid-phase extraction and quantification by GC/MS with electron impact ionization using helium as carrier gas. Quantification was performed using cocaine-d3 as internal standard in selected ion monitoring mode. The method is very simple, rapid and sensitive. The specificity, linearity, intra- and inter-assay precision and accuracy, and extraction recovery were fully evaluated. The limits of detection were 3.6 ng/mL for cocaine and 6.8 ng/mL for benzoylecgonine. The method was applied to blood samples removed at autopsy from body packers and stuffers cases in the I - IV and XV regions of Chile during 2008-2010.