@article {1491,
	title = {Analysis of amphetamine, methamphetamine and methylenedioxy-methamphetamine by micellar capillary electrophoresis using cation-selective exhaustive injection},
	journal = {Electrophoresis},
	volume = {27},
	number = {16},
	year = {2006},
	note = {ISI Document Delivery No.: 081RBTimes Cited: 18Cited Reference Count: 40Meng, Pinjia Fang, Ning Wang, Meng Liu, Huwei Chen, David D. Y.},
	month = {Aug},
	pages = {3210-3217},
	type = {Article},
	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 mu g/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.},
	keywords = {amphetamine, AMPLIFIED SAMPLE STACKING, analysis, cation-selective exhaustive injection, CHROMATOGRAPHY, CHROMATOGRAPHY-MASS SPECTROMETRY, ELECTROKINETIC, FLUORESCENCE DETECTION, illicit drug, LIQUID-CHROMATOGRAPHY, methamphetamine, methylenedioxy-methamphetamine, NEUTRAL ANALYTES, ONLINE CONCENTRATION, REVERSE MIGRATING MICELLES, SOLID-PHASE MICROEXTRACTION, ZONE-ELECTROPHORESIS},
	isbn = {0173-0835},
	url = {<Go to ISI>://000240333600007},
	author = {Meng, P. J. and Fang, N. and Wang, M. and Liu, H. W. and Chen, D. D. Y.}
}
@article {573,
	title = {Velocity-difference induced focusing of xanthine and purine metabolites by capillary electrophoresis using a dynamic pH junction},
	journal = {Chromatographia},
	volume = {57},
	number = {1-2},
	year = {2003},
	note = {ISI Document Delivery No.: 644GETimes Cited: 15Cited Reference Count: 45},
	month = {Jan},
	pages = {87-93},
	type = {Article},
	abstract = {Velocity-difference induced focusing (V-DIF) of analytes by a dynamic pH junction represents a simple yet effective on-line preconcentration method to improve concentration sensitivity in capillary electrophoresis (CE), Differences in buffer type, pH and conductivity between sample and background electrolyte (BGE) segments of the capillary are properties used to optimize purine focusing within a multi-section electrolyte system. This method permits the injection of large volumes of sample (up to 450 nL or about 18\% of capillary length), resulting in over a 50-fold improvement in sensitivity with baseline resolution. The limit of detection (S/N = 3) for xanthine is determined to less than 4,0 x 10(-8) M under optimum conditions when using UV detection. Analysis of micromolor amounts of xanthine in pooled urine is also demonstrated without sample pretreatment. A dual mechanism involving dynamic pH and isotachophoretic modes is proposed to enhance analyte focusing performance when employing buffer pH junctions based on different types of electrolyte co-ions.},
	keywords = {AMPLIFIED SAMPLE STACKING, BIOLOGICAL-FLUIDS, capillary electrophoresis, dynamic pH junction, ELECTROOSMOTIC FLOW, induced focusing, INJECTION, MICELLAR ELECTROKINETIC CHROMATOGRAPHY, NEUTRAL ANALYTES, ON-COLUMN TRANSIENT, purine metabolites, SELF-STACKING, urine, velocity-difference, VOLUME, xanthine analysis, ZONE-ELECTROPHORESIS},
	isbn = {0009-5893},
	url = {<Go to ISI>://000180908900013},
	author = {Britz-McKibbin, P. and Chen, D. D. Y.}
}
