Abstract: The invention relates to an immobilized preparation of a cell adhesion protein or peptide for cell culture having a hydrophobic cell culture substrate, a cell adhesion protein or peptide and a hydrophobic binding-adsorptive polymer to which the cell adhesion protein or peptide has been covalently bound. The hydrophobic binding-adsorptive polymer to which the cell adhesion protein or peptide is covalently bound is adsorbed to the hydrophobic cell culture substrate by hydrophobic binding and not by chemical bonding. The hydrophobic binding-adsorptive polymer is a copolymer of maleic anhydride and styrene, a copolymer of maleic anhydride and butyl vinyl ether or a copolymer of maleic anhydride and hexyl vinyl ether.