Capillary electrophoresis sequencing system

Core Capillary Electrophoresis Sequencing System Technologies. 469... 

CORE CAPILLARY ELECTROPHORESIS SEQUENCING SYSTEM TECHNOLOGIES... 

As for all synthetic products to be tested in biological systems, a careful analytical characterization of peptide libraries is crucial in order to confirm their identity and establish their quality. Compared to individual peptides, however, the analysis of peptide libraries is complicated due to the fact that the peptides are either bound to a solid support or arranged in highly complex mixtures. This poses certain restrictions on which analytical methods can be used to characterize combinatorial libraries. For example, analytical methods that are based on the separation of product components, such as high performance liquid chromatography (HPLC) and capillary electrophoresis (CE), are only of limited use for the analysis of peptide libraries, in particular of those made up of complex nnixtures (>100 peptides per mixture). The analytical methods beneficially applicable to peptide libraries include amino acid analysis, mass spectrometry, and sequencing. 

A miniaturized protein and peptide microsequencer consisting of either a fused silica capillary reactor or a microreactor made of Teflon is described. The performance of the miniaturized sequencer was evaluated by sequencing 33 and 27 picomoles of myoglobin that were covalently attached to Sequelon-DITC. The products generated by the sequencer were analyzed using capillary electrophoresis with thermo-optical absorbance detection. This CE system provides reproducible migration time (< 0.4% of RSD) and detection limits of less than 4 fmol. 

All sequencing instrument represent complex systems that requires considerable manual handling by the operator [ 14,15], Its use requires considerable experience both of the principles of operation that the various operational phases. ABI 3130 Genetic Analyzer (Applied Biosystems) is a four capillary electrophoresis system that uses fluorescently labeled dyes for detection of DNA (http //products.invitrogen.com/ivgn/product/313001). 

Biochips used for genomic analysis range from those used for separations for DNA sequencing, to those used in microvolume PCR, to complete analysis systems. Sequencing separations of single-stranded DNA fragments on a microchip follow the same principles as in conventional capillary electrophoresis. 

As seen in some of the examples given above, spectroscopic methods are very much combined with other techniques to provide more information more quickly. Optical sensors using injection-molded microfluidics systems have already been on the market for 10 years (the BiaCore), but presently the combination of spectrometers or optical sensors with microfluidics, capillary electrophoresis and DNA arrays is still very much in the center of interest For instance, an optical biosensor can be combined with mass spectroscopy, allowing very rapid sequential determination of the binding constants, charge, size and sequence of a target protein [511]. 

Tan, H. D. and Yeung, E. S. Integrated on-line system for DNA sequencing by capillary electrophoresis From template to called bases. Analytical Chemistry 69, 664—674 (1997). 

Carson, S., Cohen, A.S., Belenku, A., Ruiz-Martinez, M.C., Berka, J., and Karger, B.L., DNA sequencing by capillary electrophoresis Use of a two-laser-two-window intensified diode array detection system, AnaZ. Chem., 65, 3219,1993. 

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