title: Porous membrane-protected molecularly imprinted polymer micro-solid-phase extraction for analysis of urinary cocaine and its metabolites using liquid chromatography - Tandem mass spectrometry.
abstract: Porous membrane-protected micro-solid phase extraction (μ-SPE) using a molecularly imprinted polymer (MIP) as an adsorbent has been proposed as an integrated extraction-cleanup procedure for isolating cocaine (COC) and its metabolites [benzoylecgonine (BZE), ecgonine methyl ester (EME), and cocaethylene (CE)] from human urine. MIP beads have been synthesized using COC as a template molecule, ethylene dimethacrylate (EDMA) as a functional monomer, divinylbenzene (DVB) as a cross-linker, and 2,2'-azobisisobutyronitrile (AIBN) as an initiator. High performance liquid chromatography - tandem mass spectrometry (HPLC-MS/MS) has been used for quantifying the analytes after MIP-μ-SPE. Variables such as urine pH, adsorption temperature and time, mechanical (orbital-horizontal) stirring; and composition of the eluting solution and eluting time, were evaluated. The proposed method was shown to be precise and accurate [relative standard deviations (RSDs) of intra- and inter-day tests ranging from 3 to 8% and from 2 to 10%, respectively]; and analytical recoveries in the range of 89-100%). In addition, excellent accuracy was also verified after analyzing a FDT +25% control material for BZE. The detection limits were in the range of 0.16-1.7 ng L(-1), low enough for confirmative conclusions regarding cocaine abuse. The method was finally applied for screening/quantifying cocaine and metabolites in urine samples from poly-drug abusers.
authors.affiliation: Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, University of Santiago de Compostela, Avenida das Ciencias, s/n, 15782, Santiago de Compostela, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Sánchez-González
authors.affiliation: Department of Pathologic Anatomy and Forensic Sciences, Faculty of Medicine, University of Santiago de Compostela, Rúa de San Francisco, s/n, 15782, Santiago de Compostela, Spain.
authors.forename: María Jesús
authors.initials: MJ
authors.lastname: Tabernero
authors.affiliation: Department of Pathologic Anatomy and Forensic Sciences, Faculty of Medicine, University of Santiago de Compostela, Rúa de San Francisco, s/n, 15782, Santiago de Compostela, Spain.
authors.forename: Ana María
authors.initials: AM
authors.lastname: Bermejo
authors.affiliation: Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, University of Santiago de Compostela, Avenida das Ciencias, s/n, 15782, Santiago de Compostela, Spain.
authors.forename: Pilar
authors.initials: P
authors.lastname: Bermejo-Barrera
authors.affiliation: Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, University of Santiago de Compostela, Avenida das Ciencias, s/n, 15782, Santiago de Compostela, Spain. Electronic address: antonio.moreda@usc.es.
authors.forename: Antonio
authors.initials: A
authors.lastname: Moreda-Piñeiro
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D003042:Cocaine / Q000652:urine*; D006801:Humans; D008855:Microscopy, Electron, Scanning; D054802:Molecular Imprinting; D011108:Polymers / Q000737:chemistry*; D016062:Porosity; D015203:Reproducibility of Results; D052617:Solid Phase Microextraction / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D011108:Polymers; D003042:Cocaine
keywords: Cocaine; High performance liquid chromatography tandem mass spectrometry; Human urine; Micro-solid phase extraction; Molecularly imprinted polymer; Porous membrane-protected