Study of toxicity and peculiarities of biological effects of nanocomposite pectin-Ag: results of a subchronic experiment

Introduction. Nanocomposites synthesized by the “green chemistry” method do not contain toxic chemicals (reducing agents and organic solvents) as carriers and/or stabilizing shells. One of the representatives of this group of materials are nanocomposites based on silver, which are increasingly used in medical practice, veterinary medicine, and in some other fields. Material and methods. The nanocomposite is Ag0 nanoparticles coated with a highly methoxylated pectin shell. The concentration of Ag0 nanoparticles in the hydrosol of the pectin-Ag nanocomposite is 1.65 mmol/l, and the pectin content is 7.5 mg/ml. The size of the synthesized pectin-Ag nanocomposite is ~20-30 nm, more than 90% of the particles have a diameter of less than 20 nm, the value of the ξ-potential is 45.3 ± 0.7 mV. Toxicological studies were carried out on outbred rats. The main goal of the research was to study the toxic effects of the pectin-Ag nanocomposite in a subchronic experiment (90 days). At the end of the experiment, a complex of behavioral and clinical and laboratory parameters was determined, which made it possible to assess the biological effect of the nanocomposite on animals. The research results were statistically processed. Results. With subchronic intragastric administration of the pectin-Ag nanocomposite to laboratory animals (rats) for 3 months at doses of 50, 500, and 5000 mg/kg, it was found that the nanocomposite exhibits a dose-dependent general toxic effect with critical target organs - the liver and spleen and the main biochemical markers of toxicity effect - aminotransferase, alkaline phosphatase and lactate dehydrogenase. Conclusion. Experimental studies have made it possible to substantiate the threshold doses of the hydrosol of the pectin-Ag nanocomposite for the intragastric route of intake.