Ribonucleic Acids: Capillary Electrophoresis

With the introduction of capillary electrophoresis (CE), a new generation of electrophoretic techniques has seen the light of day. The scientiRc literature today describes a large number of applications of this powerful analytical technique in the analysis of nucleic acids. For nucleic acids, as for most other analytes, CE offers signiRcant advantages over many of the conventional electrophoretic techniques. In general, CE is characterized by short analysis time, high resolution, accuracy and reproducibility, quantitative online detection and automation. The small sample volumes required and the extreme sensitivity CE offers, represent a large analytical potential for samples of biological origin. The fundamental analytical and operational parameters for the separation of nucleic acids by CE were identiRed around 1990. A decade later, CE is considered a fully developed technology for the analysis of DNA. The rapid development of this application of CE seems to have been driven by the many practical applications of electrophoretic separation and detection of DNA in both basic and applied science. The Rrst reported analysis of RNA by CE was published in 1993 by Reyes-Engel et al. and describes the separation and quantiRcation of a speciRc messenger RNA by capillary zone electrophoresis. To date, only a limited number of articles have been published which focus on the application of CE in the analysis of RNA. The reason for this is not obvious, considering the widespread use of conventional gel electrophoresis of RNA throughout the biomedical scientiRc Reld. The fact that RNA, in many respects, displays similar characteristics as DNA, should constitute the basis for signiRcant efforts in the development of RNA analyses based on CE. However, the scientiRc literature holds promise for a substantial increase in the use of CE in RNA analyses. The following sections intend to give a basic introduction to CE of RNA, with emphasis on important analytical and operational parameters in the analyses. Finally, examples from a diverse group of applications are presented. Capillary Electrophoresis of RNA