Silver Nanoparticles Stabilized with a Chitosan Shell: Physical-Chemical Properties and Features of the Toxic Effect in Vivo

Abstract

The results of investigating the in-vivo toxicity and safety of colloidal solutions of chitosan–silver nanocomposites with different concentrations of Ag (0.19, 1.9 mg/mL) obtained by the “green chemistry” technique via the chemical reduction of silver nitrate with chitosan under hydrothermal conditions are presented. The synthesized samples possess high aggregative stability (the values of their ζ potential are 37.3 ± 0.2 and 43.2 ± 2.5 mV) and pronounced antimicrobial properties against Staphylococcus aureus, Salmonella dublin, and Escherichia coli (inhibition zones of 11–16 mm). It is found that the nanocomposites are not very dangerous in the case of acute intragastric administration, are relatively safe in the case of intraperitoneal administration, and do not possess dermal irritation. A hydrosol of the nanocomposite with a high concentration of silver (1.9 mg/mL) induces reversible eye irritation in laboratory animals as well as has a pronounced sensitizing action, inducing the development of an allergy by the delayed hypersensitivity mechanism.