Size Exclusion Chromatography

    Size exclusion chromatography separates molecules by their size. This is done by having the stationary phase be packed with small particles of silica or polymer to form uniform pores. The smaller molecules will get trapped in the silica particles and will elude from the column at a rate that is greater than that of larger molecules. Thus, the retention time depends on the size of the molecules. Larger molecules will be swept away in the mobile phase, therefore having a smaller retention time. Also notice that in this type of chromatography there isn’t any interaction, being physical or chemical, between the analyte and the stationary phase.