@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 {1230,
	title = {Separation of porphyrin-based photosensitizer isomers by laser-induced fluorescence capillary electrophoresis},
	journal = {Electrophoresis},
	volume = {26},
	number = {20},
	year = {2005},
	note = {ISI Document Delivery No.: 982VMTimes Cited: 3Cited Reference Count: 43},
	month = {Oct},
	pages = {3861-3868},
	type = {Article},
	abstract = {Methods for the separation of photosensitizer isomers, such as benzoporphyrin derivative monoacid, benzoporphyrin ethyl monoacid, 2-[1-hexyloxyethyl]-2-devinylpyropheophorbide-a, diethyleneglycol diester benzoporphyrin derivative, tin ethyl etiopurpurin, and phthalocyanine tetrasulfonate, have been systematically developed by CE. Detection was accomplished by UV absorption at 214 nm or by LIF with excitation at 442/488 nm and emission at 690 nm. The effects of three major experimental parameters of buffer types, organic solvents, and surfactant additives are described. The optimized separation conditions were determined so as to provide satisfactory separation efficiency and analysis time. The methods are shown to be suitable for the separation and determination of porphyrin and phthalocyanines regioisomers, diastereoisomers, and enantiomers.},
	keywords = {chiral additives, CHLORIN, DERIVATIVES, EFFICACY, ENANTIOMERS, FLUORESCENCE DETECTION, FRACTION, LIGHT, PANCREATIC-CANCER CELLS, PERFORMANCE LIQUID-CHROMATOGRAPHY, pharmacokinetics, PHOTODYNAMIC THERAPY, PHTHALOCYANINES, porphyrins, regioisomers},
	isbn = {0173-0835},
	url = {<Go to ISI>://000233189700008},
	author = {Peng, X. J. and Sternberg, E. and Dolphin, D.}
}
@article {574,
	title = {Complementary on-line preconcentration strategies for steroids by capillary electrophoresis},
	journal = {Journal of Chromatography A},
	volume = {1013},
	number = {1-2},
	year = {2003},
	note = {ISI Document Delivery No.: 727KJTimes Cited: 47Cited Reference Count: 4416th International Symposium on Microscale Separation and AnalysisJAN 17-22, 2003SAN DIEGO, CALIFORNIA},
	month = {Sep},
	pages = {65-76},
	type = {Proceedings Paper},
	abstract = {Complementary on-line preconcentration strategies are needed when analyzing different classes of solutes in real samples by capillary electrophoresis (CE) with UV detection. The performance of three different on-line preconcentration (focusing) techniques under alkaline conditions was examined in terms of their selectivity and sensitivity enhancement for a group of steroids, including classes of androgens, corticosteroids and estrogens. Electrokinetic focusing of large sample injection plugs (up to 28\% of effective capillary length or 22.1 cm) directly on-capillary can be tuned for specific classes of steroids based on changes in their mobility (velocity) using a multi-section electrolyte system in CE. A dynamic pH junction was applied for the selective resolution and focusing of weakly acidic estrogens using borate, pH 11.0 and pH 8.0 in the background electrolyte and the sample, respectively. Sweeping, using an anionic bile acid surfactant and neutral gamma-cyclodextrin (gamma-CD) under alkaline conditions (pH 8), resulted in focusing and separation of the moderately hydrophobic (non-ionic) classes of steroids, such as androgen and corticosteroids. Optimal focusing and resolution of all test steroids under a single buffer condition was realized by a dynamic pH junction-sweeping format using borate, pH 11.0 and bile acid surfactant with gamma-CD in the BGE, whereas the sample is devoid of surfactant at pH 8.0. The design of selective on-line focusing strategies in CE is highlighted by the analysis of microgram amounts of ethynyl estradiol derived from a female contraceptive pill extract using the dynamic pH junction method, which resulted in over a 100-fold enhancement in concentration sensitivity. (C) 2003 Elsevier B.V. All rights reserved.},
	keywords = {dynamic pH, dynamic pH junction, EPINEPHRINE, FLUORESCENCE DETECTION, INDUCED, INJECTION, MICELLAR ELECTROKINETIC CHROMATOGRAPHY, NEUTRAL ANALYTES, sample preparation, SAMPLE SELF-STACKING, SEPARATION, steroids, sweeping, TAURODEOXYCHOLATE, ZONE-ELECTROPHORESIS},
	isbn = {0021-9673},
	url = {<Go to ISI>://000185656900009},
	author = {Britz-McKibbin, P. and Ichihashi, T. and Tsubota, K. and Chen, D. D. Y. and Terabe, S.}
}
@article {3616,
	title = {Development and application of a nonaqueous capillary electrophoresis system for the analysis of porphyrins and their oligomers (PHOTOFRIN)},
	journal = {Analytical Biochemistry},
	volume = {241},
	number = {2},
	year = {1996},
	note = {ISI Document Delivery No.: VV144Times Cited: 34Cited Reference Count: 23},
	month = {Oct},
	pages = {143-150},
	type = {Article},
	abstract = {PHOTOFRIN is a complex porphyrin mixture used in the photodynamic therapy of cancer, A nonaqueous buffer with a polyether additive is used in the development of a capillary electrophoresis method for the analysis of this type of compound. This method achieves partial separation of 60 peaks for PHOTOFRIN in 30 min. A methanol-based buffer is used to improve the efficiency of the separation by decreasing the aggregation of porphyrin, and the resolution is improved by using the electroosmotic flow (EOF) to counterbalance the electrophoretic migration of the analytes. This counter-balancing EOF holds the analytes in the electric field longer, thereby improving the resolution, Brij 35 is used as a complexation reagent to adjust the selectivity and improve the efficiency of the separation, The effects that Brij 35 concentration has on the separation of both monomeric and oligomeric porphyrins are discussed. The polarity of the solvent is adjusted through the addition of water and its effect is rationalized. A qualitative fingerprinting method for characterizing PHOTOFRIN is developed, and different batches and stressed samples are studied. (C) 1996 Academic Press, Inc.},
	keywords = {ANIONS, FLUORESCENCE DETECTION, HEMATOPORPHYRIN, PHOTODYNAMIC THERAPY, PHOTOSENSITIZERS, POLYHEMATOPORPHYRIN, SEPARATION},
	isbn = {0003-2697},
	url = {<Go to ISI>://A1996VV14400001},
	author = {Bowser, M. T. and Sternberg, E. D. and Chen, D. D. Y.}
}
