title: Analysis of amphetamine, methamphetamine and methylenedioxy-methamphetamine by micellar capillary electrophoresis using cation-selective exhaustive injection.
abstract: Cation-selective exhaustive injection (CSEI) is used as an on-line concentration method for the high-sensitivity analysis of illicit amphetamines using CE. Optimum conditions for the determination of amphetamine, methamphetamine and methylenedioxy-methamphetamine were investigated. Sodium dodecyl sulfate (25 mM) in 100 mM phosphate buffer (pH 2.9) with 20% methanol as organic additive was used as the background electrolyte for CE separation. The LOD, based on an S/N of 3:1, was about 0.01 microg/mL using normal capillary micellar electrokinetic chromatography, while by using CSEI in combination with micellar sweeping the sensitivity increased up to 1000-fold with the LOD lower than 50 pg/mL. The reproducibility of CSEI combined with micellar sweeping for analyzing amphetamines was satisfactory (relative standard deviation around 10% by using area ratios against an internal standard). This method is highly sensitive and can be used to analyze trace amount amphetamines in human hair.
authors.affiliation: Department of Forensic Science, China Peoples Public Security University, Beijing, China.
authors.forename: Pinjia
authors.initials: P
authors.lastname: Meng
authors.forename: Ning
authors.initials: N
authors.lastname: Fang
authors.forename: Meng
authors.initials: M
authors.lastname: Wang
authors.forename: Huwei
authors.initials: H
authors.lastname: Liu
authors.forename: David D Y
authors.initials: DD
authors.lastname: Chen
mesh_terms: D000661:Amphetamine / Q000032:analysis*; D002412:Cations / Q000032:analysis; D000697:Central Nervous System Stimulants / Q000032:analysis*; D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D019075:Electrophoresis, Capillary / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D008694:Methamphetamine / Q000032:analysis*; D018817:N-Methyl-3,4-methylenedioxyamphetamine / Q000032:analysis*; D009862:Online Systems; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry
chemical_list: D002412:Cations; D000697:Central Nervous System Stimulants; D012967:Sodium Dodecyl Sulfate; D008694:Methamphetamine; D000661:Amphetamine; D018817:N-Methyl-3,4-methylenedioxyamphetamine