Quaternary Trimethyl Chitosan Chloride Capped Bismuth Nanoparticles with Positive Surface Charges: Catalytic and Antibacterial Activities

Quaternary trimethyl chitosan-stabilized bismuth nanoparticles (QTMC-BiNPs) with positive surface charges were uniquely synthesized and fully characterized. In the synthesis, Trimethyl Chitosan (QTMC), a water-soluble derivative of chitosan (CTS) was prepared using two-step reductive methylation. The new biopolymeric functionalized ligand further used as capping agent for synthesis QTMC-BiNPs which applied antibacterial catalytic agents. reaction carried out at room temperature without use energy consuming or high-cost instruments. QTMC nanocomposites characterized by proton nuclear magnetic resonance (1H NMR), attenuated total reflection Fourier-transform infrared, UV–visible, X-ray diffraction, photoelectron spectroscopy dispersive spectroscopic techniques. topology morphology composites examined scanning electron microscopy high-resolution transmission microscopy. Thermogravimetric differential thermal gravimetric analysis also conducted. degree quaternization dimethylation values 63.33 11.75%, respectively obtained confirmed that main product is quaternary derivative. average particle size evaluated to be between 30 45 nm. revealed clear uniform lattice fringes an estimated interplanar d-spacing 0.32 nm confirming formation highly crystalline nanocomposites. A insight into activities this nanomaterial carefully on Escherichia coli (E. coli) Staphylococcus aureus (S. aureus) resazurin based microdilution method Minimum Inhibitory Concentration (MIC) Bactericidal (MBC). results both bacteria pathogens effectively inhibited/killed very low concentrations. MIC 15.63 125 µg/mL recorded against E. S. aureus, while MBC 31.25 500.00 respectively. An extensive evaluation capability towards reduction 4-nitrophenol 4-aminophenol promising result.