SYNERGISTIC EFFECT OF MEROPENEM AND SLIVER NANOPARTICLES LOADED CHITOSAN ALGINATE HYDROGEL ON MULTI DRUG RESISTANT ACINETOBACTER BAUMANNII STRAINS FROM PATIENTS IN LAHORE, PAKISTAN

Abstract

The emergence of multidrug-resistant Acinetobacter baumannii (MDR-AB), especially strains resistant to carbapenems (CRAB), presents a significant challenge in healthcare facilities in Lahore, Pakistan, prompting the need for novel treatment approaches. This research explored the combined effect of meropenem and silver nanoparticles (AgNPs) incorporated into a chitosan-alginate hydrogel against CRAB strains from clinical samples. A total of fifty samples were obtained from tertiary hospitals in Lahore, leading to the isolation and confirmation of 20 CRAB strains through biochemical profiling, CHROM agar culture, and antibiotic susceptibility tests (AST). The chitosan-alginate hydrogels were prepared, freeze-dried, and then loaded with biogenically synthesized AgNPs and meropenem in sequence. The antibacterial activity was evaluated using disc diffusion, while In silico employed to study the interactions between the hydrogel components (chitosan, alginate, Ag⁺ clusters) and key resistance proteins (AdeRS, OmpA , OXA-23). The results showed notable synergetic combination of hydrogel, AgNPs, and meropenem produced inhibition zones of 37–43 mm, significantly larger than those achieved by monotherapy (meropenem: 16–24 mm; AgNPs: 13–20 mm; hydrogel-AgNPs: 23–31 mm),supporting the disruption of efflux, membrane integrity, and β-lactamase activity. The triple-combination hydrogel enhances the penetration of meropenem and counters resistance mechanisms in CRAB. This study introduces a promising, locally applicable therapeutic approach against the MDR-AB strains in Lahore, with potential applications for biofilm-associated infections.