Dimensional exclusion chromatography (SEC), also known as gel filtration chromatography or molecular sieves, separates molecules in the fluid phase of a liquid as it flows through a porous gel structure, depending on the physical size of the molecules in the solution. Molecules larger in diameter than the filler aperture cannot enter the hole, they are completely eliminated, quickly passed through the column, and eluted first. In the order of molecular weight and size, the smaller the diameter of the molecule, the more it can enter the pores of the packing, the larger the volume of infiltration, and the later the elution. Because dimensional exclusion chromatography (SEC) has no adsorption capacity for molecules and its separation mechanism causes dilution and elution of samples, it is generally not used in the capture phase or intermediate purification steps of the chromatography process. Sometimes it can be used as the final polishing stage, where the target protein is separated fro