Influence of Manganese on the In Vitro Biocompatible and Antibacterial Properties of Nanostructured Hydroxyapatite

Nanostructured hydroxyapatite (HA) and manganese doped hydroxyapatite (Mn-HA) was synthesized by microwave irradiation method. The structure and composition of the prepared samples were analyzed using XRD, FTIR, SEM, EDX and XPS techniques. XRD pattern of the HA and Mn-HA samples confirmed single phase hydroxyapatite. Increase in the concentration of Mn lead to the decrease of crystallinity and crystallite size along with a morphological change from platelets to rods. The in vitro drug release with an antibiotic amoxicillin showed sustained release for the Mn-HA samples, whereas the pristine HA sample shows a rapid release of the drug. The amoxicillin loaded 5Mn-HA nanorods exhibited higher antibacterial activity against Escherichia coli and Staphylococcus aureus. Also the HA and Mn-HA displayed good apatite forming ability in simulated body fluid and excellent cytocompatibility with the human osteoblast like MG-63 cells. Thus, the Mn doped HA nanorods can play a significant role in biomedical applications.