Electrochromatography monolithic capillaries

Gusev, I., Huang, X., Horvath, C. (1999). Capillary columns with in situ formed porous monolithic packing for micro high-performance liquid chromatography and capillary electrochromatography. J. Chromatogr. A 855, 273-290. 

Hoegger, D.Freitag, R. (2001). Acrylamide-based monoliths as robust stationary phases for capillary electrochromatography. J. Chromatogr. A 914, 211-222. 

Molecular imprinting has recently attracted considerable attention as an approach to the preparation of polymers containing recognition sites with predetermined selectivity. The history and specifics of the imprinting technique pioneered by Wulff in the 1970s have been detailed in several excellent review articles [122-124]. Imprinted monoliths have also received attention as stationary phases for capillary electrochromatography. 

Vegvari, A., and Guttman, A. (2006). Theoretical and nomenclatural considerations of capillary electrochromatography with monolithic stationary phases. Electrophoresis 27, 716—725. 

Capillary electrochromatography (CEC) is a miniaturized separation technique that combines aspects of both interactive chromatography and capillary electrophoresis. In this chapter, the theory of CEC and the factors affecting separation such as the stationary phase and mobile phase parameters have been discussed. The chapter focuses on the types and preparation of columns for CEC and describes the progress made in the development of open-tubular, particle-packed, and monolithic columns. The detection techniques in CEC such as the traditional UV detection and improvements made in coupling with more sensitive detectors such as mass spectrometry are also described. The chapter provides a summary of some applications of CEC in the analysis of pharmaceuticals and biotechnology products. 

Freitag, R. (2004). Comparison of the chromatographic behavior of monolithic capillary columns in capillary electrochromatography and nano-high-performance liquid chromatography. J. Chromatogr. A 1033, 267-273. 

Ratnayake, C. K., Oh, C. S., and Henry, M. P. (2000). Particle loaded monolithic sol-gel columns for capillary electrochromatography a new dimension for high performance liquid chromatography. J. High Resolut. Chromatogr. 23, 81-88. 

Quirino, J. P., Dulay, M. T, and Zare, R. N. (2001). On-line preconcentration in capillary electrochromatography using porous monolith together with solvent gradient and sample stacking. Anal. Chem. 73, 5557—5563. 

Zhang, S. H., Huang, X., Zhang, J., and Horvath, C. (2000). Capillary electrochromatography of proteins and peptides with a cationic acrylic monolith.. Chromatogr. A 887, 465 77. 

Li, Y., Xiang, R., Horvath, C., and Wilkins, J. A. (2004). Capillary electrochromatography of peptides on a neutral porous monolith with annular electroosmotic flow generation. Electrophoresis 25, 545-553. 

Lammerhofer, M., Tobler, E., Zarbl, E., Lindner, W., Svec, E, and Frechet, J. M. J. (2003). Macroporous monolithic chiral stationary phases for capillary electrochromatography new chiral monomer derived from cinchona alkaloid with enhanced enantioselectivity. Electrophoresis 24, 2986-2999. 

Chen, Z., Ozawa, H., Uchiyama, K., and Hobo, T. (2003). Cyclodextrin-modified monolithic columns for resolving dansyl amino acid enantiomers and positional isomers by capillary electrochromatography. Electrophoresis 24, 2550-2558. 

Hilder, E. R, Svec, R, and Frechet, J. M. J. (2004). Shielded stationary phases based on porous polymer monoliths for the capillary electrochromatography of highly basic biomolecules. Anal. Chem. 76, 3887-3892. 

Bedalr, M., and El Rassl, Z. (2003). Capillary electrochromatography with monolithic stationary phases III. Evaluation of the electrochromatographic retention of neutral and charged solutes on cationic stearyl-acrylate monoliths and the separation of water-soluble proteins and membrane proteins. /. Chromatogr. A 1013, 47-56. 

Ping, G. C., Zhang, W. B., Zhang, L. H., Schmitt-Kopplin, P., Zhang, Y. K., and Kettrup, A. (2003). Rapid separation of nucleosides by capillary electrochromatography with a methacrylate-based monolithic stationary phase. Chromatographia 57, 629-633. 

Allen, D., and El Rassl, Z. (2004). Capillary electrochromatography with monolithic silica columns III. Preparation of hydrophilic silica monoliths having surface-bound cyano groups chromatographic characterization and application to the separation of carbohydrates, nucleosides, nucleic acid bases and other neutral polar species.. Chromatogr. A 1029, 239—247. 

Huang, H. Y., Chiu, C. W., Huang, I. Y., and Yeh, J. M. (2004). Analyses of preservatives by capillary electrochromatography using methacrylate ester-based monolithic columns. Electrophoresis 25, 3237-3246. 

Que, A. H., and Novotny, M. V. (2002). Separation of neutral saccharide mixtures with capillary electrochromatography using hydrophilic monolithic columns. Anal. Chem. 74, 5184-5191. 

J. P. Quirino, M. T. Duylay, and R. N. Zare, On-Line Preconcentration in Capillary Electrochromatography Using a Porous Monolith Together with Solvent Gradient and Sample Stacking, Anal. Chem. 2001, 73, 5557. 

Zeng used a silica monolith modified with the liquid crystalline crown ether 29 as a column material in capillary electrochromatography (Scheme 17) [50]. Polycyclic aromatic compounds, benzenediols, pesticides, and steroids were successfully separated on the column. Introduction of the liquid crystalline crown ether led to a significant improve of the electrochromatographic performance. 

Slentz, B.E., Penner, N.A., Lugowska, E., Regnier, F., Nanoliter capillary electrochromatography columns based on collocated monolithic support structures molded in polyfdimethyl siloxane). Electrophoresis 2001, 22, 3736-3743. 

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