title: CE-MS analysis of heroin and its basic impurities using a charged polymer-protected gold nanoparticle-coated capillary.
abstract: The first application of charged polymer-protected gold nanoparticles (Au NPs) as semi-permanent capillary coating in CE-MS was presented. Poly(diallyldimethylammonium chloride) (PDDA) was the only reducing and stabilizing agent for Au NPs preparation. Stable and repeatable coating with good tolerance to 0.1 M HCl, methanol, and ACN was obtained via a simple rinsing procedure. Au NPs enhanced the coating stability toward flushing by methanol, improved the run-to-run and capillary-to-capillary repeatabilities, and improved the separation efficiency of heroin and its basic impurities for tracing geographical origins of illicit samples. Baseline resolution of eight heroin-related alkaloids was achieved on the PDDA-protected Au NPs-coated capillary under the optimum conditions: 120 mM ammonium acetate (pH 5.2) with addition of 13% methanol, separation temperature 20 degrees C, applied voltage -20 kV, and capillary effective length 60.0 cm. CE-MS analysis with run-to-run RSDs (n=5) of migration time in the range of 0.43-0.62% and RSDs (n=5) of peak area in the range of 1.49-4.68% was obtained. The established CE-MS method would offer sensitive detection and confident identification of heroin and related compounds and provide an alternative to LC-MS and GC-MS for illicit drug control.
authors.affiliation: Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, Peking University, Beijing, P. R. China.
authors.forename: Zhengxiang
authors.initials: Z
authors.lastname: Zhang
authors.forename: Bo
authors.initials: B
authors.lastname: Yan
authors.forename: Kelin
authors.initials: K
authors.lastname: Liu
authors.forename: Yiping
authors.initials: Y
authors.lastname: Liao
authors.forename: Huwei
authors.initials: H
authors.lastname: Liu
mesh_terms: D000470:Alkaloids / Q000032:analysis; D019075:Electrophoresis, Capillary / Q000379:methods*; D006046:Gold / Q000737:chemistry; D003932:Heroin / Q000031:analogs & derivatives / Q000032:analysis*; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D011095:Polyethylenes / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods
chemical_list: D000470:Alkaloids; D011095:Polyethylenes; D011108:Polymers; D000644:Quaternary Ammonium Compounds; C041004:poly-N,N-dimethyl-N,N-diallylammonium chloride; D003932:Heroin; D006046:Gold