In vivo Antibacterial Activity of Biosynthesized Selenium Nanoparticles using a Zebrafish Model

Background: Staphylococcus aureus is a leading cause of both healthcare-associated and community-acquired infections, contributing to an extensive array of illnesses, ranging from skin infections to life-threatening conditions like pneumonia and bloodstream infections. Despite extensive efforts, its resistance to multiple antibiotics poses a significant public health threat. This paper employed an experimental design to explore the potential of nanotechnology, specifically selenium nanoparticles, in combating in vivo antibacterial resistance of Staphylococcus aureus (S. aureus) infections using a zebrafish model. Materials and Methods: Selenium Nanoparticles (SeNPs) were synthesized from orange peel waste extract and sodium selenite. 93 zebrafish were infected with S. aureus via intramuscular injection and then exposed to various concentrations of SeNPs via medicated bath using Ciprofloxacin as positive control. Following the IACUC guidelines for euthanasia, fish muscle was cultured using MSA and then antimicrobial activity was noted in CFUs, or colony-forming units. Results: Results indicated significant antibacterial activity at all selenium nanoparticle concentrations, with 20 μg/mL showing the most pronounced effect, notably reducing colony counts compared to the negative control. Statistical analysis demonstrated differences between selenium nanoparticle concentrations, particularly with 15 μg/mL and 20 μg/mL having shown similar effectiveness. Conclusion: Overall, selenium nanoparticles exhibited a high level of antimicrobial activity against S. aureus, with an effectiveness rate of 95.9%.