Surface analysis and bioreactions of Ti- and V-containing a-C : H

Amorphous hydrogenated carbon films (a-C : H) containing different amounts of Ti or V were produced by combined plasma-activated chemical vapour deposition and d.c. magnetron sputtering. New bioactive materials resulted from the combination of the excellent tribological and biological properties of the a-C : H matrix with the biological response to the incorporated metals. By adding Ti to the a-C : H matrix, an enhanced differentiation of osteoblast- and reduced osteoclast-like cell activity was achieved, leading to a coating that is valuable for bone implants: enhancing bone ingrowth through increased osteoblast activity and reducing bone resorption through osteoclast-like cell inhibition. The a-C : H/V films reduced lysosomal activity as well as neutral red uptake in bone marrow cell cultures, thus being an interesting coating for short-term implants where reduced cell attachment is required. Prior to cell culture tests, the surfaces of the metal-containing a-C : H films were investigated by x-ray photoelectron spectroscopy. The relation between chemical surface composition and cellular response is discussed.