Tailoring nanocrystalline diamond coated on titanium for osteoblast adhesion

Abstract

Diamond coatings with superior chemical stability, antiwear, and cytocompatibility properties have been considered for lengthening the lifetime of metallic orthopedic implants for over a decade. In this study, an attempt to tailor the surface properties of diamond films on titanium to promote osteoblast (bone forming cell) adhesion was reported. The surface properties investigated here included the size of diamond surface features, topography, wettability, and surface chemistry, all of which were controlled during microwave plasma enhanced chemical-vapor-deposition (MPCVD) processes using CH4-Ar-H2 gas mixtures. The hardness and elastic modulus of the diamond films were also determined. H2 concentration in the plasma was altered to control the crystallinity, grain size, and topography of the diamond coatings, and specific plasma gases (O2 and NH3) were introduced to change the surface chemistry of the diamond coatings. To understand the impact of the altered surface properties on osteoblast responses, cell adhesion tests were performed on the various diamond-coated titanium. The results revealed that nanocrystalline diamond (grain sizes <100 nm) coated titanium dramatically increased surface hardness, and the introduction of O2 and NH3 during the MPCVD process promoted osteoblast adhesion on diamond and, thus, should be further studied for improving orthopedic applications.

Characteristics of Nanocrystalline Diamond Films on Titanium Surface and its Impact on the Proliferation and Adhesion of Cells

“…Moreover, the number of cells on the surface of hydrophilic NCD-o was significantly more than the control group and the NCD-h group. This result was consistent with the findings of scholars 16,17) , wherein someone confirmed that the surface of NCD-h would inhibit cell adhesion, they believed that was due to the lack of surface polar functional groups on the NCD-h surface, and the attachment of cells was the integration of cells and material surface 16) . Integrin-ligand complexes involved in cell adhesion and cell viability of the signaling, they combined the surface ligands of the material through the formation of focal adhesion 17) .…”

“…And we use SPSS Statistics 17.0 software to analyze all data. P<0.05 was considered statistically significant.…”

Biomaterial nanotopography-mediated cell responses: experiment and modeling

“…A relatively less-known orthopedic coating material, nanocrystalline diamond (NCD), has also been used recently to regulate the behavior of bone cells [48][49][50]. In particular, it was found that rationally designed NCD topography and nanoscale roughness (RMS roughness typically <25 nm) could enhance both short-term (adhesion, proliferation) and long-term functions (differentiation and bone synthesis) of osteoblast compared to micron or submicron crystalline diamond (MCD) [51][52][53].…”

Nanostructured diamond coatings for orthopaedic applications

“…5.13 (Yang et al , 2009a). In a recent study Pareta et al (Pareta et al , 2010) showed that among the H 2 , O 2 and NH 3 – plasma treated NCD, enhanced osteoblast adhesion was observed on NH 3 – plasma treated NCD. Further systematic studies might be useful to elucidate the extent to which both surface chemistry and wettability play a role in cell adhesion and growth in the case of mesenchymal stem cells.…”