Cow's Milk Silver Nanoparticles Synthesized at Various pH Combat Multidrug-Resistant

The present research aimed to explore the potential of silver nanoparticles (AgNPs) synthesized from pasteurized cow’s milk at various pH values (3, 5, 7, 9, and 11) as an antibacterial agent against clinically isolated multi-drug resistant (MDR) Pseudomonas aeruginosa ( P. aeruginosa ). The study successfully produced AgNPs at different pH levels, confirmed by transmission electron microscopy (TEM) and ultra violet (UV)-visible spectroscopy, with particle sizes ranging from 10 to 100 nm. The antibiotic sensitivity test confirmed P. aeruginosa to be multi-drug resistant. The disc diffusion method showed that AgNPs synthesized at pH 3, 7, and 9 produced inhibitory zones of 12.5-13.5 mm. Moreover, the combination of AgNPs and antibiotics demonstrated a better synergistic effect than their individual effects, with chloramphenicol and nalidixic acid exhibiting the most effective synergy. The study also found that AgNPs synthesized at pH 3, 7, and 9 were non-toxic to human embryonic kidney cell lines at 50 μl.