METODOLOGIA PARA DETERMINAÇÃO DE COCAÍNA E BENZOILECGONINA EM ÁGUAS SUPERFICIAIS

Abstract

DOI: 10.14684/intertech.13.2014.296-301

An analytical method for the determination of cocaine (COC) and benzoilecgonine (BEZ) in surface waters has been developed and validated. The method is based on extraction and purification of target compounds by solid phase extraction (SPE) followed by liquid chromatography reversed phase coupled to a tandem mass spectrometer (LC-MS/MS). Quantitative analysis was performed in a MRM (Multiple Reaction Monitoring) mode. For each analyte, two transitions between the precursor ions and ions two most abundant products were monitored; the most abundant one used for the quantitation and the other one for confirmation. Average matrix spike recoveries at three different spiking levels were 77-102 % for COC and 73-91 % for BEZ. The method quantitation limit (MQL) was 3 ng L-1 for COC and 1.2 ng L-1 for BEZ. The developed method has been applied to the analysis in the waters of public supply Guarapiranga Dam (SP, Brazil).

Index Terms - cocaine, benzoilecgonine, SPE, LC-MS/MS, surface water.