Synthesis and antimicrobial and antioxygenic properties of a water-soluble chitosan derivative with dicationic and fiber-reactive groups

Chitosan, as one of the most sustainable biomaterials in green and renewable resources, has been widely practised because of its good biocompatibility and biodegradability. However, the challenge of limited solubility of chitosan in neutral or alkaline media (pH ≥ 6.5) has been clearly pinpointed. In this study , a novel water-soluble and fiber-reactive O -[(2‑hydroxy-3-trimethylammonium)propyl] chloride oxidized chitosan ( O HACOC) was prepared with a view to developing the antibacterial finishing agent of textile fibers. The resulted O HACOC contained dicationic groups of quaternary ammonium salt groups at C6 site and amino groups at C2 position in chitosan backbone, which offered good water solubility and antibacterial activity in the wider pH ranges. The water solubility of O HACOC prepared under the optimized process can reach 23.7 g/100 mL, and its minimum inhibitory concentrations were lower than 0.0625 mg/mL against Escherichia coli and 0.125 mg/mL against Staphylococcus aureus , respectively. Meanwhile, O HACOC also showed the high antioxygenic property. This work provides ideas for the design and development of novel functional chitosan derivatives.