Magnetic Fe3O4 nanoparticles modified with tannic acid as a support for silver nanoparticles: Catalytic efficiency in procuring 1-substituted-1H-tetrazoles and investigation its therapeutic effects on mycoplasma pneumonia infected pneumonia mice model

Abstract

In this research, we present a green method for synthesizing silver nanoparticles supported on tannic acid (TA)-coated magnetic Fe₃O₄ nanoparticles (Fe₃O₄@TA). This nanocomposite functions as both reducing and stabilizing reagent. We specified the constructional and physicochemical features of the synthesized Fe₃O₄@TA/Ag NPs using several analytical tools, especially TEM, FE-SEM, EDX, elemental mapping, ICP, VSM, and XRD. For catalytic testing, we explored a 1-substituted-tetrazoles synthesis through a multicomponent reaction involving amines, triethyl orthoformate, and sodium azide in solvent-free circumstances, achieving good results. We also corroborated the catalyst stability by reusability tests across six cycles, along with hot filtration and leaching experiments. The in vivo investigation involves evaluating the P. aeruginosa lethal dose in Swiss albino mice, along with a disease manifestations analysis. This analysis includes monitoring reductions in bacteremia, body weight, hypothermia, and various other parameters throughout a 48-hour infection period. The untreated animals demonstrated a significant decline in body temperature, recorded at 25 °C after 48 h, in contrast to the initial measurement of 39 °C. Furthermore, a weight reduction of 30 % was observed by the study end. The evaluation of the efficacy of Fe₃O₄@TA/Ag NPs nanocomposite in treating lung infections was conducted through the use of calculated lethal doses, bacteremia assessments, and histopathological analyses. On day 8, the bacterial load in the Fe₃O₄@TA/Ag NPs nanocomposite group was recorded at 0.5 Log10CFU/mL, reflecting a significant reduction from the initial level of 1.5 Log10CFU/mL observed on day 1. The histopathological analysis demonstrated a pervasive and intermittent accumulation of inflammatory cells within the alveolar spaces, with infiltrates detected across all lung sections in the untreated animals. The group of animals that received treatment exhibited improved lung histology, characterized by a decrease in exudates at a dosage of 200 µg/kg. The research clearly establishes the effectiveness of Fe₃O₄@TA/Ag NPs nanocomposite in addressing lung infections caused by P. aeruginosa at a dosage of 200 µg/kg. This investigation seeks to examine the biomedical properties of these Fe₃O₄@TA/Ag NPs nanocomposite to formulate a robust treatment for this formidable pathogen.