Synergistic photodynamic antimicrobial therapy with silver nanoparticle activated by UV irradiation and 405 nm laser diode against Escherichia coli and Staphylococcus aureus

This study investigates the antibacterial properties of Moringa oleifera green-synthesized silver nanoparticles (AgNPs-MO) against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) when combined with UV radiation and a blue laser set at 405 nm. Exposure to both light treatments increased the antibacterial activity of AgNPs-MO at higher concentrations. The results indicate that photosensitizers generated from Moringa oleifera help photodynamic antimicrobial treatment work better and provide a more environmentally friendly way to manage infections. A control group (T0) was not subjected to laser irradiation, while the other three bacterial groups (A1/A2 and A3/A4) were treated to laser irradiation at different concentrations and times of silver nanoparticles. Groups A2 and A4 bacteria were also given a photosensitizer made from Moringa oleifera, and then they were exposed to varying lengths of laser light. Following incubation, a Quebec colony counter was used to measure the number of bacterial colonies. Bacterial viability was significantly reduced, according to statistical analysis utilizing a post-hoc Tukey test and a two-way ANOVA factorial test. After being exposed to mmol L^-1, mmol L^-1.5, and mmol L^-2 AgNPs-MO for 180 seconds, E. coli showed viability decreases of 70.90%, 76.44%, and 79.87%, respectively. The identical circumstances also resulted in viability decreases of 97.48%, 95.94%, and 94.72% for S. aureus. Our strategy proved to be effective, inactivating E. coli by 79.87% ± 1.92% and S. aureus by 97.48% ± 0.78% at an energy density of 3.44 J/cm². In order to battle pathogenic germs, this research proposes prospective uses for a blue laser, UV light, silver nanoparticles, and extract from Moringa oleifera.