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Rarely an eternal topic has an impact on human life as great as the healthy problem which is hotly pursued by scientists in recent years.Germs are absent nowhere,and many of them could cause the diseases and menace the health of mankind. It is an important way to improve the health level of people to sterilize and inhibit the propagation of bacteria by antibacterial materialsThe preparation of nano-silver was studied in this thesis. Silver colloids were prepared by chemical reduction method.After separating and drying ,their diameters were distributed in 10 to 20nm. By selecting the appropriate temperature, the solubility of silver nitrate and glucose, the best preparation method was determined. The reaction temperature was about 60℃while the solubility of silver nitrate and glucose were 0.01mol/land 0.02mol/lthe solubility of glucose respectively.In the application of the root canal treatment, the growth curve of Enterococcus faecalis and structural characteristics of starvation Enterococcus faecalis biofilm were studied. It was found that the growth curve of Enterococcus faecalis in BHI could be divided intolag phase, logarithmic growth phase, stable phase and starvation. By scanning electron microscopy of starvation Enterococcus faecalis biofilm, it was shown that Enterococcus faecalis had been attached to the surface of glass in 2h time while Enterococcus faecalis had been basically covered with glass and a large number of micro-colonies began to form in the 6h time; the thickness of Enterococci biofilm increased significantly in the 24h time; the spread of Enterococcus faecalis biofilm began to re-form a floating state in the 48h time. Sample A and B in the root canal treatment were synthesised. Compared with sodium hypochlorite,the MBC and the MBEC of the sample A and sample B solution to Enterococcus faecalis was observed. The MBC of Sample A, sample B, sodium hypochlorite was 0.0058%, 0.03125%, 0.625%, respectively. In starvation Enterococcus faecalis MBEC experiments, the positive control group had the growth of bacterial colonies, and the negative control group had no bacterial colony growth. The MBEC of sample A, sample B, sodium hypochlorite on 6h Enterococcus faecalis biofilm was 0.0234%, 0.0625%, 1.25%; The MBEC on 24h Enterococcus faecalis biofilm was 0.75%,> 0.5%, 2.5 %; The MBEC on 48h Enterococcus faecalis biofilm was 0.1875%,> 0.5%, 2.5%Antimicrobial efficacy of the hand disinfection production including the main anti-bacterial ingredients of ethanol, chlorhexidine acetate and silver nano particles was studied.Its antimicrobial efficacy and related properties was observed using carrier quantitative germicidal test and transmission electron microscopy (TEM). The hand disinfection production include 40%(v/v)ethanol, 5000mg/L chlorhexidine acetate and 1000μg/L silver nano-particles, diameter of silver nano-particles is less than 20nm.In vitro antimicrobial test, the average killing rate for Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, Escherichia coli exposed to this new disinfection for 1 min were >99.99%,while Salmonella typhosa needed 2 min to achieve such rates. In the vivo antimicrobial test,the result showed that the average killing rate of the right and left hands for 2min was >97.0%. So the hand disinfection production had sterilizing effect and stable performance.
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