Adhesion energy of thin collagen coatings and titanium

A polystyrene sphere coated with a thin, smooth titanium film was brought into contact with a monomeric collagen film spin-coated on a titanium substrate. The adhesion energies of the collagen monomers and the titanium were calculated from adhesion force measurements by means of atomic force microscopy. The cantilevers were modified with polystyrene spheres of different size (R=0.5 and 4.5 μm) by using a novel preparation technique. Modelling the contact mechanism, the Johnson, Kendall and Roberts model yields the best fit to the results and was therefore used to evaluate the adhesion energy. For the titanium–collagen monomer contact an adhesion energy of 56 mJ m −2 has been determined.