FTIR microscopy evaluation of the immunogenicity of eco-friendly γFe2O3@Ag@Cs nanocomposite as a platform for the discovery and screening of vaccine adjuvants

Proposed mechanism of γFe2O3@Ag NPs as adjuvant that intensify the immune response. [Display omitted] •γFe2O3@Ag@chitosan nanocomposite has been synthesized through green route.•Antibody secretion of IgG and IgM after 2 hours of γFe2O3@Ag@chitosan uptakes.•Increase of lipid, nucleic acid, and protein synthesis after uptake that varies by immune organ.•Results suggest that γFe2O3@Ag@chitosan NC (100 ug/ml) have a stimulatory effect on the immune system. Core–shell nanoparticles have been extensively researched, particularly as multimodal for medical applications. Scientists are interested in combining the optical properties of nano-plasmonic nanoparticles with the magnetic properties of super-paramagnetic nanoparticles. This combination is very important because it reduces metal toxicity and improves nanoparticle targeting. Tuning the shape and size of the nanoparticles significantly reflects their properties and applications. In previous study, we assessed the SPION@Ag@chitosan core-shell nanocomposite (γFe2O3@Ag@Cs NCs) toxicity both in vitro and preclinically in vivo, using traditional toxicological assessment and biochemical parameters. The results showed that up to100 ug/kg is a safe NP dose as evaluated by pathological and biochemical parameters. The aim of the present study was to gain insight into the effect of γFe2O3@Ag@Cs NC at sub-cytotoxic concentrations (100ug/ml) on the biochemical profile of immune organs (inguinal, axillary, spleen and thymus) by combining the investigation of cytokine secretion to ex vivo FTIR spectroscopy. The four immune organs were treated with 100 ug/kg NC and the time dependence of the effects produced by the treatment was analyzed. The Data shows that the used core-shell NC with the indicate dose have a stimulatory effect on the immune system, as evidenced by an increase in antibody secretion (IgG and IgM), lipid, nucleic acid, and protein synthesis after uptake time which depends on the specific immune organ.