Paper chromatography uses filter paper as inert support. Filter paper fiber has a strong affinity with water, which can absorb about 22% of water, and 6-7% of water is bound to the hydroxyl of cellulose in the form of hydrogen bond, which is difficult to be removed under general conditions, while the affinity between filter paper fiber and organic solvent is very weak, so in general paper chromatography, the binding water of filter paper fiber is used as the fixed phase, and the organic solvent is used as the mobile phase, when the mobile phase is along the paper When passing through the sample, the solute at the sample point is continuously distributed between water and organic phase. Part of the sample moves with the mobile phase and enters the solute free zone. At this time, it is redistributed, and part of the solute enters the stationary phase (water phase) from the mobile phase. With the continuous movement of the mobile phase, different parts are distributed according to their respective distribution coefficients, and move along the mobile phase, so that the substance can be separated and purified.
Filter paper is a kind of filter tool commonly used in chemical laboratory. Its common shape is round, mostly made of cotton fiber.
