size-exclusion chromatography
Quick Summary
Size-exclusion chromatography (SEC) is a technique used to separate molecules based on their size. In SEC, the stationary phase within the column contains a porous matrix. Larger molecules, unable to penetrate these pores, emerge from the column first. Smaller molecules, which can enter the pores, take a longer path and elute later. This method is particularly effective for separating polymers and proteins, allowing for the determination of their molecular weights and distributions. SEC is also referred to as gel-filtration chromatography when water is the mobile phase, and gel-permeation chromatography when an organic mobile phase is used. This technique can separate substances with molecular weights above 1,000.123
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- separation and purificationExclusion and clathration
Size-exclusion chromatography (SEC) has proved effective for the separation and analysis of mixtures of polymers. In this method the largest molecules emerge from the chromatographic column first, because they are unable to penetrate the porous matrix of the support. Smaller molecules appear later, because they…
Read MoreSize-exclusion chromatography (SEC) has proved effective for the separation and analysis of mixtures of polymers. In this method the largest molecules emerge from the chromatographic column first, because they are unable to penetrate the porous matrix of the support. Smaller molecules appear later, because they…
Read More - chromatographySubsequent developments
…term for such separations is size-exclusion chromatography.
Read More…term for such separations is size-exclusion chromatography.
Read More - chromatographyApplications
Size-exclusion methods are involved at molecular weights above 1,000. Field-flow fractionation extends the size range to colloids and microscopic particles.
Read MoreSize-exclusion methods are involved at molecular weights above 1,000. Field-flow fractionation extends the size range to colloids and microscopic particles.
Read More