The Antibacterial Effect of Nickel Nanoparticles Against Streptococcus mutans Compared to Chlorhexidine

Background Objectives: Due to the increasing trend of extensive antibiotic resistance among bacterial strains and side effects, seeking novel methods such as nanoparticles (NPs) is promising for infection eradication. Materials Methods: Eighteen Streptococcus mutans (S. mutans) clinical isolates were collected from dental plaques. Moreover, S. mutans ATCC25175 standard strain was obtained from Pasteur institute of Iran. Following preparation of nanoparticles, their antibacterial effects were assessed compared to chlorhexidine. The nickel NPs (Ni-NPs) was prepared and its antibacterial effect was compared to the 12% chlorhexidine. The minimum inhibitory and bactericidal concentrations (MIC and MBC, respectively) of Ni-NP (dilution range: 0.125- 64μg/mL) were measured using broth microdilution method. Results: The nickel NPs (Ni-NPs) was prepared and its antibacterial effect was compared to the 12% chlorhexidine. The minimum inhibitory and bactericidal concentrations (MIC and MBC, respectively) of Ni-NP (dilution range: 0.125-64μg/mL) were measured using broth microdilution method. The MIC and MBC levels of Ni-NP against the clinical isolates ranged 2-16μg/mL and 4-16μg/mL, respectively. These values against the S. mutans ATCC27175 standard strain included 4 and 8μg/mL, respectively. Furthermore, the MIC and MBC of chlorhexidine against clinical isolates ranged 8-64 and 32-64μg/mL, respectively, while both included 64μg/mL against standard strain (p 0.001). Conclusions: The results of this study outlined that Ni-NPs exert efficient antibacterial effect at nontoxic concentrations compared to 12% chlorhexidine.