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Characterization of Bone Cell Behaviors on Collagen Grafted Hydroxyapatite Surfaces

In order to enhance bone cell adhesion on hydroxyapatite (HA), collagen was used as a surface-grafting material on HA substrates because the collagen is a major constituent of connective tissues and has been regarded as one of the most excellent coating materials for bone bonding. First, HA disks (10mmΦ x 1mm) were prepared and then collagen was immobilbized on the HA surface using an 3-APTES coupling agent on HA disk surfaces. MC3T3-E1 osteoblasts were seeded on the collagen-grafted and non-grated HA disks and cultured in a Dulbecco’s modified eagle medium containing 10% fetal bovine serum for 4 hrs to evaluate the cell adhesion on the HA samples. The osteoblasts on the collagen-grafted sample were more spread than those on the non-grafted sample. It is believed that collagen-grafted HA surface provides suitable sites for cell attaching due to the high biocompatibility of collagen