Biosynthesized selenium nanoparticles: characterization, antimicrobial, and antibiofilm activity against Enterococcus faecalis

Background Control over microbial growth is a crucial factor in determining the success of endodontic therapy. Enterococcus faecalis is the most resistant biofilm-forming species leading to endodontic failure. Hence, the current researches are directed towards discovering materials with superior disinfection properties and lesser cytotoxicity. This study aimed to synthesize and characterize biogenically produced Selenium Nanoparticles, and to evaluate the antimicrobial and antibiofilm efficacy, against Enterococcus Faecalis, for the following test groups: Group I: Distilled water (control), Group II: SeNPs (1 mg/ml), Group III: Calcium hydroxide (1 mg/ml), Group IV: 2% Chlorhexidine gluconate (CHX), Group V: 5.25% Sodium hypochlorite (NaOCl). Materials and Methods Selenium nanoparticles were derived using fresh guava leaves (Psidium guajava) and were characterized. The antibacterial efficacy against E. faecalis was evaluated by agar well diffusion method. The antibiofilm efficacy of the test groups was observed by viable cell count, antibiofilm assay, and Anthrone and Bradford’s tests. The morphology of the biofilms was analysed using the Scanning Electron Microscope and Fourier Transform Infrared spectroscopy. Results Antibacterial and antibiofilm efficacy of all tested solutions showed superior antibacterial and antibiofilm efficacy when compared to the control group. Overall, SeNPs (Group II) was the most effective against E. faecalis biofilm, followed by NaOCl (Group V), CHX (Group IV), and Ca(OH)2 (Group III). Conclusion Biogenically produced SeNPs emerged as a novel antibacterial and antibiofilm agent against E. faecalis. This nano-formulation demonstrates the potential to be developed as a root canal disinfectant combating bacterial biofilm in endodontics after the results have been clinically extrapolated