Titanium modification by calcium ion chelated polydopamine and its cytocompatibility

Calcium ions chelation platform was successfully obtained on a titanium surface by modification with polydopamine. The chelation mechanism of polydopamine with Ca²⁺ was studied. The in vitro bioactivity and cytocompatibility of Ca²⁺ chelation platform was assessed by incubation in simulated body fluids (SBF) and cultural osteoblast cells (MC3T3-E1), respectively. The results showed that the functional groups of polydopamine chelated Ca²⁺ were changed from phenolic hydroxyl to benzoquinone. The titanium surface modified by Ca²⁺-chelated polydopamine could induce nucleation and growth of hydroxyapatite in SBF. Meanwhile, Cell attachment and viability assay demonstrated that low concentration of Ca²⁺ chelation possessed good cytocompatibility.