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Capillary Electrophoresis System (capillary + electrophoresis_system)
Selected AbstractsCover Picture: Electrophoresis 19'2010ELECTROPHORESIS, Issue 19 2010Article first published online: 29 SEP 2010 Issue no. 19 is a special issue on "CE and CEC Innovations" comprising 1 Fast Track manuscript and 20 manuscripts distributed over 5 separate parts. Part I has 5 research articles on novel trends in CEC. Part II has 4 research articles dealing with innovative methodologies. Part III reports a variety of interactive CE systems described in 5 research articles. Proteins and biomarkers are treated in 3 research articles making up part IV. The last 3 articles in this issue (Part V) are on detection approaches. The FAST TRACK article describes "An automated capillary electrophoresis system for high speed separation of DNA fragments based on a short capillary". [source] Development of a new hybrid technique for rapid speciation analysis by directly interfacing a microfluidic chip-based capillary electrophoresis system to atomic fluorescence spectrometryELECTROPHORESIS, Issue 11 2005Feng Li Abstract This paper represents the first study on direct interfacing of microfluidic chip-based capillary electrophoresis (chip-CE) to a sensitive and selective detector, atomic fluorescence spectrometry (AFS) for rapid speciation analysis. A volatile species generation technique was employed to convert the analytes from the chip-CE effluent into their respective volatile species. To facilitate the chip-CE effluent delivery and to provide the necessary medium for subsequent volatile species generation, diluted HCl solution was introduced on the chip as the makeup solution. The chip-CE-AFS interface was constructed on the basis of a concentric "tube-in-tube" design for introducing a KBH4 solution around the chip effluent as sheath flow and reductant for volatile species generation as well. The generated volatile species resulting from the reaction of the chip-CE effluent and the sheath flow were separated from the reaction mixture in a gas-liquid separator and swept into the AFS atomizer by an argon flow for AFS determination. Inorganic mercury (Hg(II)) and methylmercury (MeHg(I)) were chosen as the targets to demonstrate the performance of the present technique. Both mercury species were separated as their cysteine complexes within 64 s. The precision (relative standard deviation, RSD, n = 5) of migration time, peak area, and peak height for 2 mg·L,1 Hg(II) and 4 mg·L,1 MeHg(I) (as Hg) ranged from 0.7 to 0.9%, 2.1 to 2.9%, and 1.5 to 1.8%, respectively. The detection limit was 53 and 161 µg·L,1 (as Hg) for Hg(II) and MeHg(I), respectively. The recoveries of the spikes of mercury species in four locally collected water samples ranged from 92 to 108%. [source] DNA fragment analysis by an affordable multiple-channel capillary electrophoresis systemELECTROPHORESIS, Issue 1-2 2003Ming S. Liu Abstract We are demonstrating a cost-effective multichannel capillary electrophoresis system for a high-efficiency double-stranded DNA (dsDNA) fragments analysis. This bench-type high-performance DNA analysis (HDAÔ) system uses fluorescence-type detection with inexpensive solid-state light sources and nonmoving integrated emission collection micro-optics. DNA samples are analyzed simultaneously by using a multiple usage and disposable multicapillary cartridge, which contains integrated capillary channels, optical fibers and an integrated sieving gel reservoir. Using commercially available dsDNA size markers as indicators, the HDAÔ system provides high resolving power in 7 min separations. The system can hold a total of 192 samples in two 96-well polymerase chain reaction (PCR) plates, which can be automatically analyzed within 2.5 h. This affordable system can be used in laboratories to replace slab gel electrophoresis for routine and high-throughput dsDNA analysis. [source] Hydrophobicity-aided potentiometric detection of catecholamines, beta-agonists, and beta-blockers in a mixed-solvent capillary electrophoresis systemJOURNAL OF SEPARATION SCIENCE, JSS, Issue 1 2009Grzegorz Bazylak Abstract A series of cationic drug-like substances with distinct basicity, hydrogen-bonding ability, and hydrophobicity, including three catecholamines, two beta-agonists, and thirteen beta-blockers, was successfully detected in a capillary electrophoresis system using an end-capillary coupled potentiometric sensor consisting of a PVC-based liquid membrane deposited directly on a 100 ,m diameter copper rod. The electrophoretic separation was performed on a 72 cm×75 ,m id uncoated fused-silica capillary with an acidic background electrolyte containing phosphoric acid in a water,acetonitrile mixture, pH* 2.8. Samples were injected electrokinetically at 5.0 kV for 10 s and a running voltage of 19.5 kV was applied. Excluding the bufuralol/practolol pair, baseline separation of all substances was achieved in the developed CE system within 9 minutes. A linear relationship (R2 0.8752) between the sensitivity of the applied potentiometric detector and the parameter log P characterising the hydrophobicity of the analytes was demonstrated. The best observable limits of detection (LODs) were obtained for the highly hydrophobic substances, i. e. bufuralol (8.10×10,8 M injected concentration, S/N = 3), propranolol, alprenolol, and clenbuterol (ca. 1.10×10,7 M). In the case of hydrophilic catecholamines and carbuterol their LODs with potentiometric detection were lowered by a factor of almost one thousand, reaching a value of 6.6×10,5 M. [source] Cosegregation of a Factor VIII Microsatellite Marker with Mild Hemophilia A in Golden Retriever DogsJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 2 2005Marjory B. Brooks Mild hemophilia A (factor VIII deficiency) was diagnosed in Golden Retrievers and pedigree studies were undertaken to test the cosegregation of an intragenic factor VIII marker with the disease phenotype. The study population consisted of 30 client-owned dogs (22 males and 8 females). Hemophilic males (n = 12) typically demonstrated prolonged bleeding after trauma or surgery rather than spontaneous hemorrhagic events. The affected males had a proportionate reduction in factor VIII coagulant activity (mean FVIII:C = 4%) and factor VIII protein concentration (mean FVIII:Ag = 3%). Twenty-five dogs (10 affected males, 8 clear males, 2 obligate carrier dams, and 5 suspect carrier daughters) were genotyped for a factor VIII microsatellite marker, with allele size assigned by an automated capillary electrophoresis system. Five distinct marker alleles were present in the study pedigree and a 300-base pair allele was found to segregate with the hemophilia A phenotype. The inheritance of the hemophilia-associated allele defined carrier status for 5 suspect daughters of obligate carrier dams. The limitations inherent to linkage analyses (ie, lack of access to key family members and homozygosity at the marker locus) did not preclude carrier detection in this pedigree. We conclude that genotype analysis for the intragenic factor VIII marker can aid in control of canine hemophilia A through enhanced carrier detection. [source] Analysis of intracellular regulatory proteins by immunoaffinity capillary electrophoresis coupled with laser-induced fluorescence detectionBIOMEDICAL CHROMATOGRAPHY, Issue 2-3 2003Terry M. Phillips Abstract Measurement of intracellular regulatory proteins is of great importance in many areas of biomedical research. In this communication we describe an antibody-based capillary electrophoresis system equipped with an on-line laser-induced fluorescence detector capable of measuring intracellular proteins in cultures as low as 100 cells. The system demonstrated a high degree of precision and accuracy, being capable of detecting the fluorochrome-labeled analytes of interest at concentration of approximately 0.5,pg. We have used this instrument to study concentrations of the intracellular regulatory proteins STAT-1 and STAT-3, following stimulation of lymphocyte cultures with the inflammatory cytokine, IL-6. Using a combination of four antibodies specific for either STAT-1 or STAT-3 in both their nonphosphorylated and phosphorylated forms, we were able to demonstrate the differential expression of these proteins over time. Copyright © 2003 John Wiley & Sons, Ltd. [source] | ||||||||||