Confirmation of cocaine exposure by gas chromatography-mass spectrometry of urine extracts after methylation of benzoylecgonine.

摘要: Volatility and thermal stability are necessary physical-chemical properties for analysing a substance by gas chromatography. A derivatization step is required before chromatography of benzoylecgonine (the main metabolite cocaine). In the literature, reactions such as silylation, perfluoroalkylation or alkylation most frequently used to derivatize benzoylecgonine. However, they allow formation products sensitive moisture require purification step. So, procedure with diazomethane chromatographic analysis was evaluated. study performed evaluate efficiency conversion in cocaine, time reaction ethereal solution diazomethane. The shown be very fast mild conditions there no need further When extracted from urine solid-phase extraction derivatized diazomethane, concentrations low 25 ng/ml could detected using GC-MS full scan mode.