Size Exclusion chromatography
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- 2011.08.29
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[영문}Size Exclusion chromatography 의 정의와 방법
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Origin and definition
SEC is different from all the other HPLC methods because separations are based on physical sieving process, not on chemical attractions and interactions. The mobile phase merely acts as a solvent and eluent for the sample.
SEC has its origin in two separate groups of workers and was called by two separate names. Beginning in 1959 the name gel filtration chromatography came into use by those using aqueous mobile phase. A few years later, the name gel permeation chromatography was coined by polymer chemists separating synthetic organic polymers on polysttrene gels by using non-aqueous mobile phases. Other names werealso used, but now it seems prferable to use the term size excluzion to include both types, and the use of older terms chould be minimized.
Size Exclusion Chromatography (also known as gel filtration) separates molecules based on molecular size. This chromatography can be applied using resins or membrane. With membranes, the smaller molecules pass through while the larger molecules (above a certain size cut-off) are held above the membrane. With resins, the larger molecules pass/flow through the resin and are collected first while the smaller molecules take longer to flow through because these smaller particles get held up within the pores of the resins. Therefore, with resins, the sample passes through the resin in decreasing molecular weight. Common size exclusion applications include concentration, fractionation, desalting and buffer exchange.
Size exclusion is one of the easiest chromatography methods to perform because samples are processed using an isocratic elution.
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