“…RAMs can be classified according to the protein exclusion mechanism into the following two groups-RAM with a physical barrier (reverse phase, alkyldiol-silica material, porous silica with combined ligand) or RAM with a chemical barrier (semi-permeable surface, protein-coated silica, mixed-functional materials or shielded hydrophobic phase) [247]. Also during the development of RAM supports, enantioselective RAMs using glycopeptides antibiotics as chiral selector [250] or weak cation-exchange RAM were introduced [251].…”