Silver Nanoparticle-Aminogylcosides Conjugation for Enhanced Control of Pathogenic E. Coli O157:H7

This study ventures into unexplored realms by investigating the combined efficacy of aminoglycosides (amikacin (AMI), gentamicin (GEN), kanamycin (KAN), streptomycin (STR), and tobramycin (TOB)) and silver nanoparticles (AgNPs) against pathogenic E. coli, offering a novel approach to combating antibiotic resistance. A noticeable transformation in color from a soft yellow to a rich brown marked the transition of silver ions to AgNPs, a process visually captured over 42 h. Morphological investigations showcased untreated E. coli cells retaining their natural rod shape, contrasted by AgNP treated cells that displayed considerable structural damage, signifying compromised cellular integrity. Antibacterial experiments, involving MIC and MBC tests, unveiled an increased effectiveness of antibiotics when paired with AgNPs, demonstrating a remarkable synergistic relationship. Time-kill assays provided a bacterial reductions, highlighting the boosted antibacterial action resulting from the combined application of AgNPs and antibiotics. The combination of TOB with AgNPs displayed the most substantial biofilm reduction, reaching at 19.87%. Fascinatingly, the armA gene was observed in bacterial cultures exposed to a TOB (2MIC), but its non-detection in cultures treated with a mix of 2MIC TOB and AgNP stood out as particularly noteworthy. This research unveiled a crucial finding where the antibacterial effectiveness of aminoglycosides consistently improved when combined with AgNPs. The findings suggested a promising direction for further research into the synergistic effects of antibiotics and nanoparticle adjuncts. Understanding the underlying mechanisms of this interaction could provide valuable insights into combating bacterial resistance, particularly in strains that are resistant to conventional antibiotic treatments.