(166e) Enhanced Osteoblast Adhesion, Proliferation and Differentiation on Nanocrystalline Diamond Coatings

Osteoblast (OB, bone forming cell) functions on diamond are critical for considering the use of anti-abrasive diamond coatings on orthopedic implants. In this study, OB functions including adhesion (up to 4 hrs), proliferation (up to 5 days) and differentiation (up to 28 days) on various diamond coatings were investigated. Two kinds of diamond coatings (nano- and submicron-crystalline diamond) were fabricated through microwave plasma enhanced chemical vapor deposition and characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Surface roughness and hydrophobicity of the diamond coatings increased dramatically as grain size grew. These coatings were tested for OB adhesion and proliferation by counting adherent cells after incubation of 4hrs up to 5 days. OB differentiation on diamond coatings after incubation from 1 to 3 weeks was investigated by measuring total intracellular protein synthesis, alkaline phosphatase activity, and calcium deposition. Results demonstrated enhanced OB functions on nanocrystalline diamond coatings compared to submicron grain size coatings. The long-term (up to 3 weeks) functions of OB on nanocrystalline diamond coatings were promoted compared to submicron diamond, polished silicon and glass coverslips. In summary, these results provided insights into the application of diamond coatings in orthopedics, which can potentially improve wear problems of current implants and prolong their lifetime.