Since Francis Crick and James Watson discovered the double helical structure of deoxyribonucleic acid in 1953 , which finding-with the understanding of the basic rules of inheritance suggested by Gregor Mendel in the nineteenth century-became the theoretical basis of contemporary genetic studies, there has been an urgent need for rapid, precise, sensitive, and high-throughput analysis of nucleic acids. In the mid-1960s, electrophoresis-based methods employing polyacrylamide and agarose gels were rapidly developed; however, these were fairly time-consuming and labor-intensive techniques. The use of gels as sieving matrices for DNA electrophoresis was necessary to provide and appropriate anticonvective media and to make electric field mediated separation of nucleic acid molecules size based. Please note that the constant linear charge density of DNA chains results in practically equal charge-to-mass ratio for the different lengths oligo- and polynucleotide molecules. Slab gels are still widely used in DNAanalysis in spite of the fact that they are not quantitative, they lack online detection option and the analysis usually takes a long time. The next generation of DNA separation techniques transpired in the late 1980s by the application of capillaries to electrophoresis. This resulted in higher separation speed, as the large surface area-to-volume ratio allowed effective Joule heat dissipation (i.e., higher voltages could be applied) . In the past two decades, capillary electrophoresis (CE) became a powerful separation technique featuring automation, ease of use, and high efficiency. Novel detection methods, such as laser-induced fluorescence (LIF), increased the sensitivity of the technique, thus advancing low-level DNAanalysis from small amount of samples. The next big step toward large-scale and automated DNA analysis was the introduction of low viscosity so-called replaceable sieving polymer networks, which provided much higher flexibility compared with high viscosity cross-linked gels .
|Title of host publication||Handbook of Capillary and Microchip Electrophoresis and Associated Microtechniques, Third Edition|
|Number of pages||24|
|Publication status||Published - Jan 1 2007|
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Social Sciences(all)