多孔HAPw/n-ZnO骨修复材料的抗菌机理及抗生物膜研究

Antibiofilm and Antibacterial Mechanism of Porous HAPw/n-ZnO Bone Restorative Material

目的：评估多孔羟基磷灰石晶须/纳米氧化锌（HAPw/n-ZnO）骨修复材料在抑制细菌生物膜中的作用,并探讨其抗菌机理。方法：分别建立金黄色葡萄球菌、变形链球菌、牙龈卟啉单胞菌生物膜体外模型。无光条件在相同的多孔HAPw/n-ZnO浓度梯度（0-2g/L）下分别进行生物膜抑制试验与细胞内活性氧（ROS）检测,并利用扫描电子显微镜分析材料性能,未加入材料组作为对照。结果：无光条件下随着材料浓度递增,各浓度多孔HAPw/n-ZnO组（1.00、1.25、1.50、1.75、2.00g/L）相对于对照组（0g/L）,3种细菌的生物膜形成量（A值）逐渐减少以及细胞内活性氧（ROS）水平（荧光强度）逐渐升高,差异有统计学意义（P〈0.05）。扫描电镜图片显示,复合材料组细菌黏附减少,生物膜形成受到抑制;细胞形态异常,细胞膜受损导致内容物泄露。结论：无光条件下多孔HAPw/n-ZnO材料对金黄色葡萄球菌、变形链球菌、牙龈卟啉单胞菌生物膜均有一定程度的抑制作用,其抗菌机理之一是活性氧（ROS）的形成。

Objective：To study the antibiofilm activity and antibacterial mechanism of porous hydroxyapatite whisker（HAPw）/nano zinc oxide（n-ZnO）bone restorative biomaterial.Methods：Staphylococcus aureus,Streptococcus mutans,and Porphyromonas gingivalis biofilm model were established in vitro respectively.Under darkness,biofilm inhibition assay and intracellular reactive oxygen species（ROS）measurement were performed in the same concentration gradient（0-2mg/mL）of the porous HAPw/n-ZnO material.The scanning electron microscope was employed to analyze the material.Without porous HAPw/n-ZnO,inoculums was used as control.Results：As the material concentration increases,each concentration of porous HAPw/n-ZnO group（1.00,1.25,1.50,1.75,and 2.00mg/mL）relative to the control（0mg/mL）,three kinds of oral bacteria biofilm formation exhibited a gradual decrease and an increased intracellular ROS level under darkness.The difference was statistically significant（P〈0.05）.Scanning electron microscopy（SEM）images revealed that the treatment of the material decreased the bacteria adhesion and three kinds of biofilm formation.Composite material group exhibited abnormal bacteria morphology and bacterial cell membrane destruction,which caused the leakage of intracellular contents.Conclusion：Porous HAPw/n-ZnO materials has a certain degree of inhibition under darkness on staphylococcus aureus,streptococcus mutans,and Porphyromonas gingivalis biofilm,and one of its antibacterial mechanism is the formation of reactive oxygen species（ROS）.