Background: Incoherent use of antibiotics has led toward resistance in MRSA, becoming
multidrug-resistant with a high rate of virulence in the community and hospital settings.
Objective: Synergistic anti-MRSA activity was investigated in this study for hybrid material composite
spheres of amoxicillin, Ag nanoparticles, and chitosan, which were prepared by one-step synthesis
method, and various characterizations were performed.
Methods: Antimicrobial-susceptibility assay on MRSA was achieved by disc diffusion and agar dilution
techniques, while agar well diffusion was used for hybrid composite spheres. The in vitro and
cytotoxicity studies were conducted on the skin abrasion mouse model and MTT assay on RD cell,
Results: All isolates showed resistance to the tested antibiotics except vancomycin. MIC against
MRSA showed high resistance with amoxicillin from 4 to 128 mg L-1. The mean diameter of chitosan
spheres and Ag nanoparticles was 02 mm and 277 nm, respectively. Morphology of spheres
was uneven, varied, porous, and irregular in SEM, and Ag nanoparticles presence and formation
was also seen in the micrograph. No substantial interface among drug, nanoparticles, and polymer
was found in XRD, and IR showed characteristic peaks of all compounds in the formulation. The
in vitro assay showed augmented anti-MRSA activity with amoxicillin loaded hybrid composite
spheres (22-29 mm). A significant reduction in microbial burden (~6.5 log10 CFU mL-1) was seen
in vivo with loaded hybrid composite spheres formulation. The MTT assay indicated no potential
cytotoxicity with hybrid composite spheres.
Conclusion: The synergistic effect of Amoxycillin in the current study predicts a promising hybrid
formulation with enhanced anti-MRSA activity.