中文摘要：

目的探讨纳米银离子对表皮葡萄球菌（Staphk，lococcusepidermidis）生物膜（biofilm）结构的影响。方法采用摇床法，以纳米银离子含量不同的乙烯．醋酸乙烯酯（ethylene．vinylacetate，EVA）塑料为细菌粘附载体，建立体外生物膜模型；将培养2d的标本分别放在扫描电子显微镜（scanningelectronmicroscopy，SEM）和荧光显微镜下观察空白组与纳米银离子干预组生物膜的形成情况；荧光探针SYT09／PI标记生物膜内细菌、激光共聚焦显微镜（confocallaserscanningmicroscopy，CLSM）结合生物膜图形结构分析软件（imagestructureanalyze，ISA）分析纳米银离子作用后1d、2d组生物膜的结构变化。结果2d组生物膜经SEM和荧光显微镜检测，纳米银离子干预组相比空白对照组，细菌变得稀疏，结构明显受到破坏，多糖产量减少。CLSM下观察可见经纳米银离子干预后生物膜菌落变稀疏，孔道变多；ISA软件分析结果显示，2d时空白对照组与0．1％纳米银离子干预组生物膜厚度、平均扩散距离（averagediffusiondistance，ADD）$H结构熵（textualentropy，TE），分别为17．55±2．08和10．80±1．68；3．56±0．54和1．85±0．06；5．29±0．57和2．72±0．39（P〈0．05）；区域孔率（arealporosityAP）为0．90±0．02和0．98±0．01（P〈0．05）。0．05％纳米银离子组其作用效应没有0．1％纳米银离子组明显。1d组生物膜也有相同的趋势。结论纳米银离子可破坏表皮葡萄球菌生物膜的结构，高浓度组较低浓度组效果明显。

英文摘要：

Objective To analyze the effect of silver nanoparticle on the structure of Staphylococcus epidermidis biofilm. Methods The ethylene-vinyl acetate （EVA） plastics in different concentration of silver nanoparticle was used as carriers for the bacteria adhesion. The Staphylococcus epidermidis biofilm model in vitro was built by shaking method. The specimens was cultured for 2d and then respectively examined by scanning electron microscop （SEM） and fluorescence microscope. The ld, 2d biofilm were stained with SYTO9/PI, monitored by confocal laser scanning microscope （CLSM）. Quantification of the effect was calculated by image structure analyzer （ISA） software. Results After adding silver nanopartical, the 2d biofilm was thin and abnormal compared with the control by SEM detection. The extracellular polymeric substances （EPS） in biofilm was significantly decreased after intervention with silver nanopartical, which was visulalized by fluorescence microscope. The quantitative data from ISA software showed that the control and the 0.1% of silver nanopartical, the thickness, average diffusiondistance（ADD） and textual entropy（TE） were 17.55±2.08 and 10.80±1.68; 3.56±0.54 and 1.85±0.06; 5.29±0.57 and 2.72±0.39（P〈0.05）. Areal porosity（AP） was 0.90±0.02 and 0.98±0.01 （P〈0.05）. 0.05% of silver nanopartical has not the obvious effect compared with the 0.1% of silver nanopartical. The 1 d biofilm showed the same tendency. Conclusion The structure of Staphylococcus epidermidis biofilm can be destroyed by silver nanoparticle and high concentration has better effect than low concentration.