High performance capillary electrophoresis instrument

High performance capillary electrophoresis was introduced originally as an analytical tool. Now that instruments are equipped with automated fraction collection, however, capillary electrophoresis can be used for micropreparative collection of individual peaks separated from a mixture. Using the fraction collection feature, nanomolar amounts of solute such as proteins, peptides, oligonucleotides can be collected in amounts sufficient for microsequencing. An intersample washing procedure and use of well-formed capillaries aid in the prevention of artifacts.44... 

Capillary electrophoresis employing chiral selectors has been shown to be a useful analytical method to separate enantiomers. Conventionally, instrumental chiral separations have been achieved by gas chromatography and by high performance liquid chromatography.127 In recent years, there has been considerable activity in the separation and characterization of racemic pharmaceuticals by high performance capillary electrophoresis, with particular interest paid to using this technique in modem pharmaceutical analytical laboratories.128 130 The most frequently used chiral selectors in CE are cyclodextrins, crown ethers, chiral surfactants, bile acids, and protein-filled... 

CEC is often inappropriately presented as a hybrid method that combines the capillary column format and electroosmotic flow employed in high-performance capillary electrophoresis with the use of a solid stationary phase and a separation mechanism, based on specific interactions of solutes with the stationary phase, characteristic of HPLC. Therefore CEC is most commonly implemented by means typical of both HPLC (packed columns) and CE (use of electrophoretic instrumentation). To date, both columns and instrumentation developed specifically for CEC remain scarce. 

El Rassi, Z. (1996). High Performance Capillary Electrophoresis of Carbohydrates, Beckman Instruments., p. 102... 

High performance capillary electrophoresis is one form of free-solution electrophoresis. CE is useful to researchers and analysts working in areas in which traditional electrophoresis is customarily applied (e.g., biopolymer analysis) and also in disciplines not usually associated with electrophoretic analysis, such as inorganic ion analysis. The potential application areas of CE are vast, because this technique can separate a variety of ligates, from inorganic ions up to intact cells, using the same instrumental hardware designed for separations based on different physical-chemical mechanisms. 

Smith RD, Udseth HR, Barinaga CJ, Edmonds CG (1991) Instrumentation for high-performance capillary electrophoresis-mass spectrometry. J Chromatogr 559 197-208. 

One of the most important features of the capillary electrophoresis instrument is the detection system. Several of the detection methods commonly used in high-performance liquid chromatography have been somewhat adapted for capillary electrophoresis. Currently, the most popular detection methods developed for capillary electrophoresis are summarized in Table III. 

T Wehr, M Zhu, R Rodriguez, D Burke, K Duncan. High performance isoelectric focusing using capillary electrophoresis instrumentation. Am Biotech Lab. 8 22-29 1990. 

Another implementation of SIA systems in high-performance separation methods is instrumental hyphenation with HPLC or capillary electrophoresis instruments. This is... 

Figure 9.6 Surfer-generated chromatoeletropherogram of fluorescamine-labeled tryptic digest of ovalbumin. Reprinted from Analytical Chemistry, 62, M. M. Bushey and J. W. Jorgenson, Automated instrumentation for comprehensive two-dimensional high-performance liquid chromatography/capillary zone electrophoresis, pp 978-984, copyright 1990, with permission from the American Chemical Society.

The spectrum of new analytical techniques includes superior separation techniques and sophisticated detection methods. Most of the novel instruments are hyphenated, where the separation and detection elements are combined, allowing efficient use of materials sometimes available only in minute quantities. The hyphenated techniques also significantly increase the information content of the analysis. Recent developments in separation sciences are directed towards micro-analytical techniques, including capillary gas chromatography, microbore high performance liquid chromatography, and capillary electrophoresis. 

High performance liquid chromatography (HPLC) and capillary electrophoresis (CE) are two instrumental separation techniques that are applicable to the separation of proteins and peptides. The advantage of HPLC and CE techniques is that they afford the analyst the freedom to resolve a complex mixture by different routes employing different... 

Parallel to the development of mass spectrometric instrumentation and methodologies, the improvements of separation techniques, such as gas chromatography (GC), high performance liquid chromatography (HPLC) and capillary electrophoresis (CE), and of their coupling with MS allowed the study of complex mixtures, that are generally encountered in most studies. 

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