Sample Preparation of Urine Samples Prior to CE-MS in Toxicological Analysis  

作　　者：Rovini Michele Schappler Julie Kohler Isabelle Anzini Mauriziot Veuthey Jean-Luc Rudaz Serge 

机构地区：[1]Dipartimento Farmaco Chimico Tecnologico, Universith di Siena, via Aldo Moro, 53100 Siena, Italy [2]School of Pharmaceutical Sciences, University of Geneva, Bd d ＇Yvoy 20 1211 Geneva 4, Switzerland [3]Swiss Centre for Applied Human Toxicology, University of Geneva, CMU, Rue Michel-Servet 1, 1211 Geneva 4, Switzerland

出　　处：《Journal of Chemistry and Chemical Engineering》2011年第7期583-594,共12页化学与化工（英文版）

摘　　要：Capillary electrophoresis （CE） coupled with mass spectrometry （MS） with a sheath liquid interface is nowadays recognized as a powerful separation technique for drugs and metabolites analysis in human urine and can be applied in numerous fields such as clinical toxicology, drug substitution monitoring, forensic sciences and antidoping. With an acidic background electrolyte containing 15 mM ammonium formate at pH 2.5 and a sheath liquid consisting in a mixture of isopropanol/water （50：50, v/v） with 0.5% formic acid, CE-ESI-MS in positive mode demonstrated excellent performance for simultaneous analysis of basic drugs of abuse and metabolites in urine （e.g. cocaine, amphetamine, morphine and phase II metabolites）. To achieve the desired level of sensitivity, two injection modes and three sample pre-treatments were evaluated. The detection of basic drugs and phase Ⅱ metabolites in diluted urine was achieved at concentrations above 1μg/mL. In order to enhance sensitivity, a sample preparation was required. A liquid-liquid extraction （LLE） was compared with solid-phase extraction. LLE was performed at alkaline pH and samples were electrokinetically injected. A chemometric approach （Doehlert design） was carried out in order to determine optimized injection parameters. Limits of detection （LOD） down to 10 ng/mL were reached with field-amplified sample injection but phase II metabolites were not extracted. Therefore, instead of LLE a SPE was performed on C 18 sorbent, and elution fraction after washing step containing phase Ⅱ metabolites was loaded on mixed-mode anion exchanger cartridges. After electrokinetic injection, this two-step SPE allowed LOD ca. 10 ng/mL for drugs and phase Ⅱ metabolites.

关 键 词：Capillary electrophoresis mass spectrometry sample preparation URINE toxicology. 

分 类 号：TQ444[化学工程—化学肥料工业] TS207.3[轻工技术与工程—食品科学]