Investigations into the biocompatibility of nanohydroxyapatite coated magnetic nanoparticles under magnetic situation

Regenerative medicine consisting of cells and materials offers a new approach for repairing and regenerating the organs and tissues. More and more researches focused on the magnetic nanobiomaterials due to its superior advantages to traditional materials. However, the toxicity of nanosized magnetic particles cannot be ignored, especially under the magnetic situation. This study aims to study the biocompatibility of nanohydroxyapatite (n-HA-) coated magnetic nanoparticles under the magnetic situation. n-HA-coated magnetic nanoparticles were fabricated through an ultrasound-assisted coprecipitation method. Subsequently, these materials were analyzed by transmission electron microscope (TEM) and X-ray diffraction (XRD) and then were cultured with mesenchyme stem cells derived from human bone marrow (hMSC-BM). In vitro experiment proved the satisfactory biocompatibility of n-HA-coated magnetic nanoparticles. These important factors (ALP, OCN, and OPN) influence the osteogenic differentiation of hMSC-BM. It was found that the hMSC-BM with combination of n-HA/Fe₃O₄ and magnetic stimulation presented higher degree of osteoblast-related markers than that in each alone. This research demonstrated that a novel nanohydroxyapatite coated magnetic nanoparticle is safe under the magnetic situation. Therefore, these n-HA-coated magnetic nanoparticles are promising biomagnetic materials for future applications.