Synthesis and characterization of Fe3O4?ZnS:Mn nanocomposites for biomedical applications

Fe3O4?ZnS:Mn nanocomposites were prepared by two combined chemical precipitation routes and further characterized to prove the formation of composite structure. The formation mechanism was discussed according to sequential steps of the composite formation. The crystalline structure, morphology and magnetic properties of nanocomposites were identified by XRD, TEM-HRTEM and VSM analyses respectively. The presence of ZnS:Mn shell on Fe3O4 surface was confirmed by XPS, EDX and EPR. The potential cytotoxicity of Fe3O4?ZnS:Mnx% nanocomposites has been investigated using human skin melanoma (A375) and normal human keratinocytes (HaCaT) cell lines. The cellular uptake on human skin melanoma (A375) was evidenced by CLFM and revealed that Fe3O4?ZnS:Mnx% nanocomposites penetrated the cells through endocytosis, in a concentration dependent manner. Hyperthermia measurements evidenced that Fe3O4?ZnS:Mnx% nanocomposites are adequate for magnetic hyperthermia applications. Except the latest case the Fe3O4?ZnS:Mnx% platforms are safe to use for biomedical applications as they show toxicity starting only from high concentration.