Synthesis and performance optimization of dual-modified chitosan Derivatives: Effects of novel zwitterionic and quaternary ammonium groups on antibacterial, antioxidant, and biocompatibility properties

Abstract

In this study, a series of halogenated zwitterionic-quaternary ammonium chitosan derivatives were synthesized through a dual-modification strategy. Their structures were confirmed by Fourier-transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (¹H NMR), thermogravimetric analysis (TGA), and X-ray diffraction (XRD) analyses. Antibacterial assays demonstrated that these derivatives possess broad-spectrum activity against Escherichia coli and Staphylococcus aureus, with favorable MIC, MBC, and inhibition rate values. Antioxidant evaluations revealed improved radical-scavenging capacity compared to native chitosan. Furthermore, CCK-8 cytotoxicity and hemolysis tests confirmed their excellent biocompatibility, with no detectable toxicity. Collectively, these derivatives exhibit promising antibacterial, antioxidant, and biosafety properties, underscoring their broad potential for applications in food preservation, biomedical materials, and cosmetics.

Keywords: Antibacterial activity; Antioxidant activity; Biocompatibility; Chitosan; Dual modification.