The full name is hydroxypropyl glucan gel. Sephadex lh-20 is the product of Sephadex g-25 (one of the commercial models of dextran gel according to crosslinking degree) after hydroxypropyl treatment. At this time, the glucose part of dextran gel molecule will combine with hydroxypropyl into the following ether bond form: -oh → -och2ch2ch2oh. Compared with Sephadex G, the total number of -oh groups in Sephadex lh-20 molecules did not change, but the proportion of carbon atoms was relatively increased. Therefore, Sephadex lh-20 can be used not only in water, but also in polar organic solvents or mixed solvents composed of them and water.