Abstract
Background: Ag+ and Zn2+ have already been used in combinations to obtain both enhanced antibacterial effect and low cytotoxicity. Despite this, it is still unclear how the Zn2+ co-works with Ag+ in the synergistic antibacterial activity. The main purposes of this study were to investigate the co-work pattern and optimum ratio between Ag+ and Zn2+ in their synergistic antibacterial activity against E. faecalis, the possible mechanisms behind this synergy and the primary application of optimum Ag+-Zn2+ co-work pattern against the E. faecalis biofilm on dentin. A serial of Ag+-Zn2+ atomic combination ratios were tested on both planktonic and biofilm-resident E. faecalis on dentin, their antibacterial efficiency was calculated and optimum ratio determined. And the cytotoxicity of various Ag+-Zn2+ atomic ratios was tested on MC3T3-E1 Cells. The role of Zn2+ in Ag+-Zn2+co-work was evaluated using a Zn2+ pretreatment study and membrane potential-permeability measurement. Results: The results showed that the synergistically promoted antibacterial effect of Ag+-Zn2+ combinations was Zn2+ amount-dependent with the 1:9 and 1:12 Ag+-Zn2+ atomic ratios showing the most powerful ability against both planktonic and biofilm-resident E. faecalis. This co-work could likely be attributed to the depolarization of E. faecalis cell membrane by the addition of Zn2+. The cytotoxicity of the Ag+-Zn2+ atomic ratios of 1:9 and 1:12 was much lower than 2% chlorhexidine. Conclusions: The Ag+-Zn2+ atomic ratios of 1:9 and 1:12 demonstrated similar strong ability against E. faecalis biofilm on dentin but much lower cytotoxicity than 2% chlorhexidine. New medications containing optimum Ag+-Zn2+ atomic ratios higher than 1:6, such as 1:9 or 1:12, could be developed against E. faecalis infection in root canals of teeth or any other parts of human body.
Original language | English (US) |
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Article number | 10 |
Journal | Journal of Nanobiotechnology |
Volume | 16 |
Issue number | 1 |
DOIs | |
State | Published - Jan 31 2018 |
Keywords
- Antibacterial
- Biofilm
- Dentin
- E. faecalis
- Ion
- Silver
- Zinc
ASJC Scopus subject areas
- Bioengineering
- Medicine (miscellaneous)
- Molecular Medicine
- Biomedical Engineering
- Applied Microbiology and Biotechnology
- Pharmaceutical Science