Control of EOF in CE by different ways of application of radial electric field

Small, dense low-density lipoprotein (sdLDL) has been accepted as an emerging cardiovascular risk factor, and there has been an increasing interest in analytical methods for sdLDL profiling for diagnosis. Serum sdLDL may be measured by different laboratory techniques, but all these methods are laborious, time-consuming, and costly. Recently, we have demonstrated that a low-temperature bonding of quartz microfluidic chips for serum lipoproteins analysis (Zhuang, G., Jin, Q., Liu, J., Cong, H. et al., Biomed. Microdevices 2006, 8, 255-261). In contrast to this previous study, we chose SDS as anionic surfactant to modify both lipoproteins and the channel surface to minimize lipoprotein adsorption and improve the resolution of lipoprotein separation. Two major LDL subclass patterns including large, buoyant LDL (lLDL), sdLDL, and high-density lipoprotein (HDL) were effectively separated with high reproducibility. RSD values of the migration time (min) and peak areas of standard LDL and HDL were 6.28, 4.02, 5.02, and 2.5%, respectively. Serum lipoproteins of 15 healthy subjects and 15 patients with coronary heart disease (CHD) were separated by microchip CE. No peaks of sdLDL were detected in serum samples of healthy subjects while sdLDL fractional peaks were observed in patients' entire serum samples. These results suggested that the microchip-based sdLDLs assay was a simple, rapid, and highly efficient technique and significantly improved the analysis of CHD risk factors.

Section: Lipoprotein Fractional Peak Identificationmentioning

confidence: 99%

Microchip‐based small, dense low‐density lipoproteins assay for coronary heart disease risk assessment

Wang

Jin

et al. 2008

“…In addition to chemical ways, EOF can be regulated also by physical tool, external radial electric field applied to the outer low-conductive capillary coating as shown by CE separation of oligoglycines [95].…”

Section: Suppression Of Adsorption and Control Of Eofmentioning

confidence: 99%

Recent developments in CE and CEC of peptides

Kašička

2007

Self Cite

118

The article brings a comprehensive survey of recent developments and applications of high-performance capillary electromigration methods, zone electrophoresis, ITP, IEF, affinity electrophoresis, EKC, and electrochromatography, to analysis, preparation, and physicochemical characterization of peptides. New approaches to the theoretical description and experimental verification of electromigration behavior of peptides and to methodology of their separations, such as sample preparation, adsorption suppression, and detection, are presented. Novel developments in individual CE and CEC modes are shown and several types of their applications to peptide analysis are presented: conventional qualitative and quantitative analysis, purity control, determination in biomatrices, monitoring of chemical and enzymatical reactions and physical changes, amino acid and sequence analysis, and peptide mapping of proteins. Some examples of micropreparative peptide separations are given and capabilities of CE and CEC techniques to provide important physicochemical characteristics of peptides are demonstrated.

“…The surface modification involved surface oxidation by plasma, the silanization of 3‐aminopropyldimethylethoxysilane and immobilization of poly L ‐glutamic acid) via amide bond. In addition to chemical ways, EOF can be regulated also by physical tool, external electric field applied to the outer low‐conductive capillary coating, as shown by CE separation of oligoglycines 98.…”

Section: Suppression Of Adsorption and Control Of Eofmentioning

confidence: 99%

Recent advances in CE and CEC of peptides (2007–2009)

Kašička

2009

The review presents a comprehensive survey of recent developments of high-performance capillary electromigration methods, zone electrophoresis, ITP, IEF, affinity electrophoresis, EKC and electrochromatography, and their application to analysis, preparation and physicochemical characterization of peptides. New approaches to the theoretical description and experimental investigation of electromigration properties of peptides, and to methodology of their separations, such as sample preparation, adsorption suppression, EOF control and detection, are described. New developments in particular CE and CEC modes are reported and several types of their applications to peptide analysis are presented: conventional qualitative and quantitative analysis, determination in biomatrices, monitoring of chemical and enzymatical reactions and physical changes, amino acid and sequence analysis, and peptide mapping of proteins. Few examples of micropreparative peptide separations are shown and capabilities of CE and CEC techniques to provide important physicochemical characteristics of peptides are demonstrated.