Smardex G-25 is a gel filtration medium prepared by cross-linked dextran. Size exclusion chromatography (SEC), also called Gel filtration (GF), separates molecules on the basis of differences in size as they pass through a SEC medium packed in a column. SEC media consists of spherical particles with pores of different sizes where molecules small enough to enter the pores are retarded as compared to larger molecules. Samples are eluted by single buffer. Buffer conditions can be varied to suit the sample type or the requirements for the next purification, analysis, or storage step. Smartdex G-25 is well established gel filtration medium for desalting, removing contaminants and buffer exchange in industrial applications.