Development and characterisation of novel Ce-doped hydroxyapatite–Fe3O4 nanocomposites and their in vitro biological evaluations for biomedical applications

Hydroxyapatite (HAP: Ca10(PO4)6(OH)2) is extensively used in biomedical field because of its biocompatibility, osteoconductivity and non-toxicity properties. However, HAP exhibits poor mechanical strength and bacterial restriction behavior. To overcome these drawbacks, various metal ions such as Ag+, Zn2+, Cu2+, Ti4+ and Ce4+/3+ are incorporated in HAP matrix to increase the mechanical and biological properties. Among these, Cerium (Ce) is selected as antibacterial agent due to its high thermal stability and its applications in dental fillings, bone healing and catheters. Fe3O4 nanoparticles were used in hyperthermia treatment, magnetic fluid recordings and catalysis. In this present study, we have synthesized nanocomposites consisting of 1.25% Ce doped HAP with various concentrations of Fe3O4 NPs as 90:10 (C-1), 70:30 (C-2) and 50:50 wt% (C-3) using ball milling technique. The obtained Ce@HAP-Fe3O4 nanocomposites were characterized by ATR-FTIR, XRD, VSM, SEM-EDAX and TEM analysis. Further, the fabricated Ce@HAP-Fe3O4 nanocomposites were tested for its antibacterial activity towards Staphylococcus aureus (S. aureus) and Escherichia coli (E.coli), where C-3 composites exhibit the excellent pathogen inhibition towards E.coli. In addition, the cytotoxicity evaluation on C-3 nanocomposites by in vitro biocompatibility study using MG-63 cells shows the prominent viable cell enhancement up to 400µg/mL concentrations.