Grafting of bioactive polymers onto titanium surfaces and human osteoblasts response

In this paper, the adhesion of human osteoblast- like cells (line MG63) onto functionalized pure Titanium (Ti cp) has been studied. The Titanium surfaces were functionalized by grafting bioactive polymers bearing anionic groups such as sodium sulfonate. The grafting was achieved under inert atmosphere, by radical polymerization of sodium styrene sulfonate NaSS after the activation of the surface. ATR/FTIR and XPS were used to analyse the chemical composition of the grafted and non grafted titanium surfaces. The efficiency of the grafting was evidenced by the high amounts of grafted polyNaSS (5mug/cm²), measured by Toluidin Blue colorimetric method. Biological tests have been investigated to highlight the influence of the grafting polymer on the cell response. Human osteoblast-like cells were cultured on titanium surfaces. Differences in the adhesion strength of cells were observed. Mineralization of osteoblast-like cells was studied after 28 days of culture and the amount of calcium formed were evaluated. Surface modification by bioactive polymers bearing anionic groups appears as an effective way to stimulate the bone regeneration over that, as provided by titanium as suggested by basic studies and in vitro results.