Hyperthermia effect and antibacterial efficacy of Fe 3+ /Co 2+ co‐substitutions in β‐Ca 3 (PO 4 ) 2 for bone cancer and defect therapy

The combined effect of cobalt and iron substitutions in β ‐Ca 3 (PO 4 ) 2 as a potent material for application in hyperthermia and as a bone substitute is presented. Structural analysis reveals the preferential accommodation of Co 2+ and Fe 3+ at the Ca 2+ (5) sites of β ‐Ca 3 (PO 4 ) 2 until the limit of ∼10 mol % and, thereafter, prefer Ca 2+ (4) lattice sites. Occupancy of both the Co 2+ and Fe 3+ ions induces a significant contraction of the β ‐Ca 3 (PO 4 ) 2 unit cell. The Co 2+ /Fe 3+ co‐substitutions in β ‐Ca 3 (PO 4 ) 2 display magnetic characteristics that enhances hyperthermia effect. In addition, the presence of Co 2+ in β ‐Ca 3 (PO 4 ) 2 enunciates pronounced antibacterial efficacy against tested microorganisms. Nevertheless, the enhanced level of Co 2+ in β ‐Ca 3 (PO 4 ) 2 results to induce significant toxicity. The biocompatibility of the synthesized thermoseeds is verified from the hemolytic tests and cytotoxicity test performed on human sarcoma cell line MG‐63. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1317–1328, 2018.