Capillary Electrophoresis of Nucleic Acids

Abstract

AbstractCapillary electrophoresis (CE) is a powerful and relatively new technique for nucleic acid mapping, and can be used along with conventional slab electrophoresis and high‐performance liquid chromatography (HPLC). There are several types of separation techniques of CE, for instance capillary zone electrophoresis (CZE), micellar electrokinetic chromatography (MEKC), capillary gel electrophoresis (CGE), and capillary affinity gel electrophoresis (CAGE), all of which are capable of being used for quantification and qualification of nucleic acids. CZE and MEKC are suitable for the separation of bases, nucleoside and nucleotide monomers, and short nucleic acids. Although the sensitivity of ultraviolet (UV) detection is not as high as HPLC, since the light path length of CE is more than 100 times smaller than that of HPLC, a laser‐excited fluorescence detection system enables highly sensitive detection of nucleic acids. CGE and CAGE, in which electrophoresis is performed in molecular sieving materials of polymer gels, are used rather than HPLC and slab gel electrophoresis (SGE) for sequencing of large nucleic acids for several reasons: high‐resolution power, high‐speed sequencing, ease of automation, and small sample volume. Combining the advantages of CGE and laser fluorescence detection with a four‐ or two‐color labeling method enables sequencing of more than 1000 bases within 1 h. Moreover, recent improvements in capillary array electrophoresis (CAE) with high‐throughput and high‐speed sequencing systems contribute to an expansion of the sequence analysis of DNA fragments in order to achieve the goal of the Human Genome Project (HGP).