Cytocompatibility of TiAlC, TiSiC, and TiAlN: Tests and First-Principles Calculations.

Herein, the cytocompatibility of selected MAX phases, TiAlC, TiSiC, and TiAlN, were systematically evaluated using tests for the first time. These phases were anoxic to preosteoblasts and fibroblasts. Compared with the strong viable fibroblasts, the different cellular responses of these materials were clearly distinguishable for the preosteoblasts. Under an osteoblastic environment, TiAlN exhibited better cell proliferation and differentiation performance than TiAlC and TiSiC. Moreover, the performance was superior to that of a commercial Ti-6Al-4V alloy and comparable to that of pure Ti. A possible mechanism was suggested based on the different surface oxidation products, which were determined from the binding energy of adsorbed Ca ions using first-principles calculations. Compared with the partially oxidized TiCO layer on TiAlC and TiSiC, the partially oxidized TiNO layer on the TiAlN had a stronger affinity to the Ca ions, which indicated the good cytocompatibility of TiAlN.