This study introduces a new approach for enhancing immunity toward mucosal vaccines. HEV71 killed vaccine that is formulated with nanosize calcium phosphate adjuvant and encapsulated onto chitosan and alginate delivery carriers was examined for eliciting antibody responses in serum and saliva collected at weeks 0, 1, 3, 5, 7 and 9 for viral-specific IgA & IgG levels and viral neutralizing antibody titers. The antibody responses induced in rabbits by the different formulations delivered by a single (buccal) route were compared to those of dual immunization (intradermal / mucosal) and un-immunized control. Chitosan-loaded vaccine adjuvant induced elevated IgA antibody, while Alginate-adjuvant irreversible bonding sequestered the vaccine and markedly reduced immunogenicity. The induced mucosal and parenteral antibody profiles appeared in an inverse manner of enhanced mucosal IgA antibody accompanied by lower systemic IgG following a single oral immunization route. The combined intradermal and oral dual-immunized group developed an elevated salivary IgA, systemic IgG, and virus neutralizing response. A reduced salivary neutralizing antibody titer was observed and attributed to the continual secretion exchanges in saliva. Designing a successful mucosal delivery formulation needs to take into account the vaccine delivery site, dosage, adjuvant and carrier particle size, charge, and the reversibility of component interactions. The dual immunization seems superior and is a important approach for modulating the antibody response and boosting mucosal protection against HEV71 and similar pathogens based on their transmission mode, tissue tropism and shedding sites. Finally, the study has highlighted the significant role of dual immunization for simultaneous inducing and modulating the systemic and mucosal immune responses to EV71.
UV and solar-based photocatalytic degradation of 2,4-dichlorophenol (2,4-DCP) as an organic contaminant in ceramics industry wastewater by ZnS and Fe-doped ZnS NPs was the focus of this research. Nanoparticles were prepared using a chemical precipitation process. The cubic, closed-packed structure of undoped ZnS and Fe-doped ZnS NPs was formed in spherical clusters, according to XRD and SEM investigations. According to optical studies, the optical band gaps of pure ZnS and Fe-doped ZnS nanoparticles are 3.35 and 2.51 eV, respectively, and Fe doping increased the number of carriers with high mobility, improved carrier separation and injection efficiency, and increased photocatalytic activity under UV or visible light. Doping of Fe increased the separation of photogenerated electrons and holes and facilitated charge transfer, according to electrochemical impedance spectroscopy investigations. Photocatalytic degradation studies revealed that in the present pure ZnS and Fe-doped ZnS nanoparticles, 100% treatment of 120 mL of 15 mg/L phenolic compound was obtained after 55- and 45-min UV-irradiation, respectively, and complete treatment was attained after 45 and 35-min solar light irradiation, respectively. Because of the synergistic effects of effective surface area, more effective photo-generated electron and hole separation efficiency, and enhanced electron transfer, Fe-doped ZnS demonstrated high photocatalytic degradation performance. The study of Fe-doped ZnS's practical photocatalytic treatment capability for removing 120 mL of 10 mg/L 2,4-DCP solution made from genuine ceramic industrial wastewater revealed Fe-doped ZnS's excellent photocatalytic destruction of 2,4-DCP from real industrial wastewater.