COVALENT ATTACHMENT OF CELL-ADHESIVE, (ARG-GLY-ASP)-CONTAINING PEPTIDES TO TITANIUM SURFACES

A three-step reaction procedure was applied to introduce RGD-containin g peptides on the titanium surface. Water-vapor-plasma-pretreated tita nium surfaces were first silanized with (3-aminopropyl)-triethoxysilan e, resulting in a multilayer film of poly(3-aminopropyl)siloxane. In a second reaction step, the free primary amino groups were linked to on e of the three hetero-cross-linkers: N-succinimidyl-6-maleimidylhexano ate, N-succinimidyl-3-maleimidylpropionate, and N-succinimidyl ans-4-( maleimidylmethyl)cyclohexane-1-carboxylate. Onto the resulting termina l-maleimide surface, two model, cell-adhesive peptides, H-Gly-Arg-Gly- Asp-Ser-Pro-Cys-OH and H-Arg-Gly-Asp-Cys-OH were immobilized through c ovalent addition of the cysteine thiol (-SH) group. X-ray photoelectro n spectroscopy, infrared reflection absorption spectroscopy, and radio labeling techniques were applied to characterize the surfaces. From in dependent quantitative analysis, an approximate coverage of 0.2 simila r to 0.4 peptides/nm(2) was calculated.