Determination of Cocaine and Metabolites in Urine Using Electrospray LC/MS

A rapid, simple, and sensitive electrospray LC/MS method has been developed for the quantitative analysis of cocaine and benzoylecgonine in urine using electrospray with the Agilent 1100 LC/MSD system. Urine samples were extracted using solid phase extraction cartridges, and the drug and metabolite were analyzed without derivatization using an isocratic separation and selected ion monitoring (SIM). Drug Testing Matthew H. Slawson and Kimberly J. Shaw Center for Human Toxicology, University of Utah John M. Hughes Agilent Technologies Application Note Introduction Cocaine has two metabolites, benzoylecgonine (BE) and norcocaine, that are frequently analyzed as markers of cocaine use. The well-established GC/MS analysis of cocaine and BE requires derivatization of the metabolite. Derivatization adds additional variables from the derivatization process and can also introduce aggres-sive derivatizing reagents into the analytical system. These basic molecules show excellent sensitivity in electrospray mass spectrometry, and the analysis of cocaine and both metabolites can be carried out without a derivatization step. The same solid-phase extraction (SPE) developed for the GC/MS analysis can be used for the LC/MS analysis.