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The bonded phase filler of silica gel matrix has good mechanical strength, chemical stability and thermal stability. The surface of silica gel is rich in silicon hydroxyl (si-oh), which is the main adsorption point and the most reactive functional group on the surface of silica gel. It is also the basis of surface chemical bonding or modification. The surface of silica gel was modified by chemical modification, and the various bonding phases obtained were suitable for different separation modes.