Electrophoresis analytical aspects

Hyphenation in capillary electrophoresis is still in its infancy. Critical aspects of CE hyphenation include the minute volumes of sample injected (typically a few nL) and small flow-rates (in the order of nLmin-1). Interfaces are not commercially available. CZE-UV can be used for the analysis of higher polyamide oligomers in HF1P solution [859]. A solvent elimination design with nebuliser has been described for CE-FTIR and CEC-FTIR coupling absolute detection limits are hundreds of pg [860]. An advantage of CE-FTIR is that analytes may be detected and identified without derivatisation. CE(C)-NMR [861-863] is advancing rapidly. 

Within the last 25 years, capillary electrophoresis (CE) has developed as a high-resolution analytical technique that has been apphed to all analytical helds including chemical, pharmaceutical, biomedical, forensic, environmental analysis, and food sciences. Based on the number of publications, drugs are actually the preferred analytes in CE. While they served as model compounds for the investigation of specific aspects in some studies, CE has been used to solve real pharmaceutical problems in the majority of applications. 

Hannig, Kurt. New aspects in preparative and analytic continuous free-flow cell electrophoresis. GIT Lab.-Med., 3(5) 235, 1982. 

Techniques for detection and quantitation of zones are an important aspect of electrophoretic analysis. The most common approaches to detection involve the use of stains, autoradiography of radio-labelled analytes, or immunoreaction with specially prepared antisera. In the case of electrophoresis in free solution, on-line detection devices can be used. 

You will probably be familiar with the analytical uses of paper chromatography or TLC (thin-layer chromatography) from other branches of chemistry. Here we will consider mainly those aspects of chromatography and electrophoresis most relevant to biomolecules. After completing this chapter you should be able to ... 

The availability of increasingly sensitive analytical techniques for separating proteins, notably electrophoresis (see also Appendix 15), in the 1960s gradually revealed that more and more of the familiar mainstream enzymes, e.g. those of the glycolytic pathway occur in more than one form in the body. It is now clear that very often there are separate genes encoding these isoenzymes. Often there can be more than one form of an enzyme in the same tissue, but, even so, one of the obvious aspects of isoenzymes is that different tissues tend to have different distributions of the different forms. 

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