纳米银离子对表皮葡萄球菌生物膜形成过程的影响  

Effect of silver nanoparticle on the growth kinetics of Staphylococcus epidermidis biofilm

作　　者：刘维勤[1] 余加林[1] 刘官信[1] 郜向娜[1] 朱秀菊[1] 刘立婷[1] 

机构地区：[1]重庆医科大学附属儿童医院新生儿诊治中心儿童发育疾病研究省部共建教育部重点实验室,重庆400014

出　　处：《中国微生态学杂志》2011年第10期870-873,共4页Chinese Journal of Microecology

基　　金：国家自然科学基金(30772363);2008教育部博士基金(20070631001);重庆市科委自然基金(2007BB5282);重庆医科大学08校级重点项目(XBZD200808)

摘　　要：目的探讨纳米银离子对表皮葡萄球菌(Staphylococcus epidermidis)生物膜(biofilm)形成过程的影响。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-Vinyl acetate,EVA)塑料为细菌粘附载体,建立体外生物膜模型;将各个时间点培养好的标本放在扫描电子显微镜(Scanning Electron Microscopy,SEM)及倒置显微镜下观察空白组与纳米银离子干预组中生物膜的形成情况,并结合NIS-Element BR软件计算生物膜覆盖率(biofilm coverage rate,BCR);荧光探针SYTO9/PI标记生物膜内细菌、激光共聚焦显微镜(Confocal LaserScanning Microscopy,CLSM)结合生物膜图形结构分析软件(Image Structure Analyze,ISA)观察纳米银离子作用后各时间点生物膜的结构变化。结果 2 d组生物膜经SEM检测,纳米银离子干预组较空白对照组相比,细菌变稀疏,结构明显受到破坏。BCR检测,0.5 d时纳米银离子干预组较空白对照组相比差异没有统计学意义,但在1 d、2 d时BCR差异有统计学意义(P<0.05)。CLSM结合ISA软件分析结果显示,2 d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(average diffusion distance,ADD)和结构熵(textual entropy,TE),分别为17.55±2.08和11.33±0.98、3.12±0.30和1.93±0.13、5.79±和3.17±0.16(P<0.05);区域孔率(Areal porosity,AP)为0.90±0.01和0.98±0.01(P<0.05)。但5 d时2组参数之间差异没有统计学意义。0.05%纳米银离子组也有相同的趋势。结论纳米银离子对表皮葡萄球菌的形成有抑制作用,但随着时间的推移,其抗菌作用逐渐减弱。高浓度组较低浓度组抗菌效果更加明显,持续时间更长。Objective To analyze the effect of silver nanoparticle on the growth kinetics of Staphylococcus epidermidis biofilm. Method Ethylene-vinyl acetate （EVA） plastics in different concentrations of silver nanoparticle were used as the carriers for bacteria adhesion. Staphylococcus epidermidis BF model in vitro was built by shaking method. The specimens were cultured for 2 days and examined by Scanning Electron Microscopy （SEM）. At 0.5, 1 and 2 days after cultivation, the biofilm was stained with crystal violet and examined with a digital microscope to calculate the biofilm coverage rate （BCR） by NIS-Element BR. The 0.5, 1,2, 3 and 5 d biofilms were marked with SYTOg/PI, observed by Confocal Laser Scanning Microscope （CLSM）. Quantification of the effect was calculated by Image Structure Analyzer （ISA） software. Result After adding Silver nanoparticles, the 2 d biofilm was thin and abnormal compared with the control by SEM detection. At 1 and 2 d after cultivation, the BCR in biofilm was significantly decreased after intervention with silver nanoparticles. However the 0.5 d biofilm had no difference in different concentrations of silver nanoparticle. The quantitative data from ISA software showed that the 2 d biofilm＇s depth, average diffusion distance （ADD） and textual entropy （TE） of the control and 0.1% of silver nanoparticle groups were 17.55 ± 2.08 vs 11.33 s 0.98, 3.12 s 0.30 vs 1.93 ± 0. 13, and 5.79 ±0.23 vs 3.17 ±0.16 （P 〈0.05） , respectively. The Areal porosities （AP） were 0.90 s0.03 vs 0.98 ＋0.01 （ P 〈 0.05 ）. But the 5 d biofilms had no difference in different concentrations of silver nanopartiele. 0.05% of silver nano- particle showed the same tendency. Conclusion The growth kinetics of Staphylococcus epidermidis biofilm can be delayed by silver nanoparticles. With the development of time, the antibacterial effect eventually decreases. High concentration has better antibacterial effect than low concentration.

关 键 词：表皮葡萄球菌 生物膜 纳米银离子 

分 类 号：R378.11[医药卫生—病原生物学]