title: Synthesis, characterization, antimicrobial activity and mechanism of a novel hydroxyapatite whisker/nano zinc oxide biomaterial.
abstract: Postoperative infections remain a risk factor that leads to failures in oral and maxillofacial artificial bone transplantation. This study aimed to synthesize and evaluate a novel hydroxyapatite whisker (HAPw) / nano zinc oxide (n-ZnO) antimicrobial bone restorative biomaterial. A scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and x-ray diffraction (XRD) were employed to characterize and analyze the material. Antibacterial capabilities against Staphylococcus aureus, Escherichia coli, Candida albicans and Streptococcus mutans were determined by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), and kinetic growth inhibition assays were performed under darkness and simulated solar irradiation. The mode of antibiotic action was observed by transmission electron microscopy (TEM) and confocal laser scanning microscopy (CLSM). The MIC and MBC were 0.078-1.250 mg ml(-1) and 0.156-2.500 mg ml(-1), respectively. The inhibitory function on the growth of the microorganisms was achieved even under darkness, with gram-positive bacteria found to be more sensitive than gram-negative, and enhanced antimicrobial activity was exhibited under simulated solar excitation compared to darkness. TEM and CLSM images revealed a certain level of bacterial cell membrane destruction after treatment with 1 mg ml(-1) of the material for 12 h, causing the leakage of intracellular contents and bacteria death. These results suggest favorable antibiotic properties and a probable mechanism of the biomaterial for the first time, and further studies are needed to determine its potential application as a postoperative anti-inflammation method in bone transplantation.
authors.affiliation: Department of Stomatology, Kunming General Hospital of Chengdu Military Region, #212 Daguan Road, Xishan District, Kunming, Yunnan Province, People's Republic of China. Clinical College of Kunming Medical University, Kunming, People's Republic of China.
authors.forename: Jian
authors.initials: J
authors.lastname: Yu
authors.forename: Wenyun
authors.initials: W
authors.lastname: Zhang
authors.forename: Yang
authors.initials: Y
authors.lastname: Li
authors.forename: Gang
authors.initials: G
authors.lastname: Wang
authors.forename: Lidou
authors.initials: L
authors.lastname: Yang
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Jin
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Chen
authors.forename: Minghua
authors.initials: M
authors.lastname: Huang
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry*; D000893:Anti-Inflammatory Agents / Q000737:chemistry; D001672:Biocompatible Materials / Q000737:chemistry*; D001842:Bone and Bones / Q000187:drug effects / Q000378:metabolism; D002176:Candida albicans / Q000187:drug effects; D017886:Durapatite / Q000737:chemistry*; D004926:Escherichia coli / Q000187:drug effects; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry; D007249:Inflammation / Q000188:drug therapy; D008027:Light; D008826:Microbial Sensitivity Tests; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D053761:Nanocomposites; D049329:Nanostructures / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D011208:Powders; D013211:Staphylococcus aureus / Q000187:drug effects; D013295:Streptococcus mutans / Q000187:drug effects; D013696:Temperature; D014961:X-Ray Diffraction; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D000890:Anti-Infective Agents; D000893:Anti-Inflammatory Agents; D001672:Biocompatible Materials; D011208:Powders; D011092:Polyethylene Glycols; D017886:Durapatite; D006861:Hydrogen Peroxide; D010100:Oxygen; D015034:Zinc Oxide