*3.6.4 Macroporous adsorption resin chromatography*

It is a chromatographic method which combines the principle of adsorption and molecular sieve. Its chromatographic behavior possesses reversed-phase properties. Macroporous resin is a kind of solid macromolecule material with no dissociable group and porous structure and is insoluble in water. It is widely used in the separation and enrichment of natural compounds because of its stable physical and chemical properties (insoluble in acids, bases, and organic solvents).

In practical work, the water solution of the mixture to be separated is usually washed by water, water-containing alcohol solution with low to high concentration. The mixture can be separated into several components. The regeneration of macroporous adsorbent resin is convenient. It is often washed by 1 mol/L hydrochloric acid and 1 mol/L sodium hydroxide solution, respectively, first, then washed by distilled water to neutral, and stored in methanol or ethanol. The alcohol should be washed out with distilled water before using.
