银纳米对不同骨科生物材料上金黄色葡萄球菌生物膜的影响

Effect of silver nanoparticles on Staphylococcus aureus biofilm formation on different orthopedic biomaterials

目的观察银纳米颗粒(silver nanoparticle,AgNP)的抑制细菌生物膜特性,并研究其在常用的3种骨科生物材料上的抑制生物膜作用。方法通过微孔板内药敏试验培养确定AgNP的最低抑制浮游菌浓度(minimal inhibitory concentration,MIC)和最低抑制生物膜浓度(minimal biofilm inhibitory concentration,MBIC)。在钛合金、氧化钛和不锈钢3种骨科生物材料上培养金黄色葡萄球菌(ATCC 25923)生物膜,使用32、16、8、4、2、0μg/mL AgNP干预生物膜,确定AgNP在3种材料上的MBIC。分析扫描电子显微镜结果,并通过测定光密度值观察AgNP对生物膜形成的影响。结果微孔板内AgNP的MIC和MBIC均为16μg/mL。在对内植物的生物膜抑制实验中,AgNP在氧化钛中MBIC为16μg/mL,在钛合金和不锈钢中MBIC为32μg/mL。3种材料中,氧化钛上光密度值最低,钛合金上光密度值最高。结论AgNP具有强大的抗细菌生物膜特性,能够在体外阻止金黄色葡萄球菌生物膜形成。钛合金上生物膜形成最多,而氧化钛上最少,不锈钢则介于两者之间。

Objective To observe the inhibitory characteristics of silver nanoparticles(AgNP)on bacterial biofilms and investigate their inhibitory effect on biofilm formation on three common orthopedic biomaterials.Methods The minimal inhibitory concentration(MIC)and minimal biofilm inhibitory concentration(MBIC)of AgNP were determined by microplate dilution assay.Biofilms of Staphylococcus aureus(ATCC 25923)were cultured on three orthopedic biomaterials(titanium alloy,titanium oxide,and stainless steel)and intervened with AgNP at concentrations of 32,16,8,4,2 and 0μg/mL to determine the MBICs on the three materials.The effects of AgNP on biofilm formation were analyzed by scanning electron microscopy and measuring optical density.Results The MIC and MBIC of AgNP in the microplate assay were both 16µg/mL.The MBICs of AgNP on biofilm formation in titanium oxide,titanium alloy,and stainless steel were 16μg/mL,32μg/mL,and 32μg/mL,respectively.Among the three materials,the lowest optical density was observed on titanium oxide,while the highest was on titanium alloy.Conclusions AgNP has strong antibacterial biofilm characteristics and can prevent the formation of Staphylococcus aureus biofilm in vitro.Biofilm formation is most pronounced on titanium alloy,least on titanium oxide,and intermediate on stainless steel.