Abstract:
Extensive utilization of silver nanoparticles have raised concerns of their effects on biological
systems. Silver nanoparticles often showing great antimicrobial potential often cannot pass the
safety because of their unknown toxicity profile. Nanoparticles synthesized from biological source
have additive advantage over chemical source owing to reduction in cytotoxicity. Various
synthesis approaches have been developed for the fabrication of silver nanoparticles used for
specific application. In vivo assessment hence plays a key role to unveil their effects and
interaction with biological system. Current study is designed to compare already biosynthesized
nanoparticles for their efficacy and safety profile and screen out the nanoparticles showing highest
efficacy profile. Violacein capped silver nanoparticles (VNPs), Starch capped silver nanoparticles
(CNPs), Aerva javanica silver nanoparticles (AjNPs), Heliotropium crispum silver nanoparticles
(HcNPs), and zinc oxide nanoparticles (ZnNPs) were used for this study. The radical scavenging
potential of these five nanoparticles were analyzed through H2O2 radical scavenging assay which
showed the concentration dependent scavenging activity of nanoparticles. This was followed by
the evaluation of their safety profile by performing MTT assay. Histological analysis of these
nanoparticles were done through H&E staining to assess the morphological changes in liver, spleen
and kidney of the balb/c mice (n=100). Doses ranging from 3mg/kg to 24 mg/kg were given
intraperitoneally on daily basis for 28 days and effects were monitored. VNPs showed highest
mortality and morbidity rate along with tissue damage as compared to rest of nanoparticles. The
in vivo activity of these nanoparticles were studied in balb/c mice (n=40) with an infected partial
thickness burn (2nd degree). The burned area was seeded with CFUs of 2x108
of Methicillin
resistant Staphylococcus aureus and Pseudomonas aeruginosa. AjNPs along with HcNPs were
Abstract
xiv
screened to pass these experiments and found out to be more efficacious and safe for their use as
antimicrobials and disinfectants.
