纳米银对多菌种生物膜中粪肠球菌的杀菌作用

目的:研究纳米银对多菌种生物膜中粪肠球菌的杀菌作用.方法:用粪肠球菌、产黑色素普雷沃菌以及具核梭杆菌构建多菌种生物膜85 个.分别用0.1%(12~15 nm、100 nm)纳米银悬浊液以及2%的次氯酸钠溶液处理,然后通过qPCR方法检测样本中粪肠球菌的活菌量和粪肠球菌的细菌总量.配对t检验比较各组细菌样本临界循环数(Ct).结果:各个实验组使用和不使用PMA之间粪肠球菌的细菌计数有着差别(P=0.000);将3 个实验组使用和不使用PMA qPCR检测到的Ct值的差值进行比较:纳米银(12~15 nm)实验组最大,纳米银(100 nm)实验组次之,次氯酸钠实验组最小(P<0.05).结论:纳米银对于多菌种生物膜中的粪肠球菌有着较强的杀菌作用,直径较小的纳米银杀菌作用较强.

Bactericidal effect of nano-silver against E.faecalis growing in multi-species biofilm

Objective:To evaluate the bactericidal effects of nano-silver against Enterococcus faecalis(E.faecalis) growing in multi-species biofilm.Methods:85 biofilms were established using MBECTM P&G Assay with E.faecalis together with Fusobacterium nucleatum and P.melaninogenica.Thereafter,10 specimens were used as the controls,75 were randomly divided into 3 groups(n=25),and treated with 0.1% nano-silver (12-15 nm) solution,0.1% nano-silver (100 nm) solution and 2% hypochlorite solution,respectively.Each sample was then separated into 2 different tubes.PMA was added to one of the tubes,and the other was left untreated.Then,DNA extraction and qPCR were performed.The cycle threshold(Ct) values between samples were compared by paired t test.Results:The Ct values of the samples treated with PMA were higher than that without PMA(P=0.000) in the group of 0.1% nano-silver solution(12-15 nm)was higher than that in the group of 0.1% nano-silver solution(100 nm)and 2% sodium hypochlorite solution.(P<0.05);the value in the group of 0.1% nano-silver solution(100 nm)was larger than that in 2% sodium hypochlorite solution(P<0.05).Conclusion:0.1% nano silver solution might have a strong bactericidal effect against against E.faecalis growing in multi-species biofilm.The bactericidal effect may be enhanced with the small size of silver particles.