Titanium containing amorphous hydrogenated carbon films (a-C : H/Ti): surface analysis and evaluation of cellular reactions using bone marrow cell cultures in vitro

Amorphous hydrogenated carbon (a-C:H) coatings, also called diamond-like ca rbon (DLC), have many properties required for a protective coating material in biomedical applications. The purpose of this study is to evaluate a new surface coating for bone-related implants by combining the hardness and in ertness of a-C : H films with the biological acceptance of titanium. For th is purpose, different amounts of titanium were incorporated into a-C:H film s by a combined radio frequency (rf) and magnetron sputtering set-up. The X -ray photoelectron spectroscopy (XPS) of air-exposed a-C:H/titanium (a-C:H/ Ti) films revealed that the films were composed of TiO2 and TiC embedded in and connected to an a-C:H matrix. Cell culture tests using primary adult r at bone marrow cell cultures (BMC) were performed to determine effects on c ell number and on osteoblast and osteoclast differentiation, By adding tita nium to the carbon matrix, cellular reactions such as increased proliferati on and reduced osteoclast-like cell activity could be obtained, while these reactions were not seen on pure a-C :H films and on glass control samples. In summary, a-C:H/Ti could be a valuable coating for bone implants, by sup porting bone cell proliferation while reducing osteoclast-like cell activat ion. (C) 2000 Elsevier Science Ltd. All rights reserved.