Fabrication of HAP/Ag/SSD ternary nanocomposite and its antibacterial properties

Hydroxyapatite/silver/silver sulfadiazine ternary nanocomposite (HAP/Ag/SSD TNC) with a novel hierarchical structure was successfully fabricated as following steps. First, mesoporous hydroxyapatite (HAP) nanorods as carrier were synthesized by a facile hydrothermal method. Second, as one antibacterial agent, silver nanoparticles were designed to be loaded on the mesoporous HAP nanorods to produce HAP/silver nanorods. Third, silver sulfadiazine as the other antibacterial agent was in situ produced on the surface of HAP/silver nanorods to form HAP/Ag/SSD TNC. To estimate its antibacterial properties, minimum inhibitory concentration, minimal bactericidal concentration, and a filter paper inhibition zone experiments were conducted with three bacteria strains of gram-negative Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa), and gram-positive Staphylococcusaureus (S. aureus). The results demonstrated that HAP/Ag/SSD TNC exhibited outstanding and sustained antibacterial activities against P. aeruginosa in 48 h. Toward E. coli and S. aureus, HAP/Ag/SSD TNC displayed similar antibacterial abilities with that of HAP/silver nanorods. Therefore, HAP/Ag/SSD TNC has the potential to be a new excellent antibacterial agent and extensively applied in the antibacterial field.