Super-paramagnetic nanostructured CuZnMg mixed spinel ferrite for bone tissue regeneration

Spinel ferrite-based nanoparticles are being widely applied in bone tissue regeneration because of their outstanding properties such as their capability to be applied in hyperthermia-based bone cancer therapy. In the present study, Cu_0.3Zn_0.2Mg_0.5Fe₂O₄ nanoparticles are synthesized through thermal-treatment method followed by calcination at 650 °C. The calcined nanoparticles are characterized through X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) equipped with energy dispersive spectroscopy (EDS) and elemental mapping, Fourier transform infrared spectroscopy (FTIR), and vibrating sample magnetometer (VSM). Then from the nanoparticles, a disk is fabricated and sintered at 800 °C to assess Cu_0.3Zn_0.2Mg_0.5Fe₂O₄ basic requirements of a bone substitute like apatite-formation ability, degradation, mechanical properties, and cell compatibility and so compressive strength, apatite forming ability up to 21 days in simulated body fluid (SBF), in vitro degradation in two different buffers, antibacterial activity, cell compatibility, and attachment are assessed in vitro. The results show that the magnetization saturation (Ms) is increased from 52 to 60 emu/g when the nanoparticles are sintered at 800 °C. Immersion the disk into SBF is synchronized with deposition of spherical CaP particles on the surface of disk and the XRD after soaking period proves that the depositions are hydroxyapatite. The degradability of disk is assessed into phosphate buffer saline (PBS) and citric acid buffer (CAB) up to 21 days. A gram-positive and a gram-negative bacteria are used to assess the disk's antibacterial activity and the disk exhibits acceptable activity against both of them. The cell compatibility and attachment of disk in the exposure of MG63 cell line are assessed up to 7 days and the results prove high cell compatibility of the disk.