High-Throughput Electrospinning System| Latest research progress on antibacterialproperties of chitosan-based nanofibers

Prof. Xiaoming Zhao & Prof. Yuanjun Liu (Tiangong University): Latest Research Progress on Antibacterial Properties of Chitosan-Based Nanofibers

Chitosan is widely sourced, offering excellent biocompatibility, biodegradability, non-toxicity, antibacterial properties, high safety, and environmental friendliness. Due to the presence of amino groups in chitosan, it readily protonates into a polyelectrolyte under acidic conditions. During electrospinning, this increases repulsion between polymer ionic groups, leading to bead formation and difficulty in jetting from the needle, resulting in poor spinnability of chitosan-containing spinning solutions. To address this, polyvinyl alcohol (PVA), polyethylene oxide (PEO), or other spinning aids are often added to interact with chitosan via hydrogen bonds, reducing electrostatic repulsion and surface tension to improve spinnability. Concurrently, incorporating various antibacterial agents not only resolves spinning challenges but also enhances the nanofibers' antibacterial performance.

Recently, Prof. Xiaoming Zhao and Prof. Yuanjun Liu’s team at Tiangong University published their latest research, "Latest research progress on antibacterial properties of Chitosan-based nanofibers," in Chemical Engineering Journal. The study first outlines factors influencing chitosan’s antibacterial properties: the impact of chitosan sources, intrinsic factors, structural modifications, and crosslinkers on mechanical and antibacterial performance. It then details progress in chitosan-based binary and ternary antibacterial systems. Finally, the challenges in commercializing electrospun chitosan nanofibers are analyzed, alongside future directions for chitosan-based antibacterial nanofibers.

Fig. 1: Diverse forms of chitosan.

Chitosan can be obtained or prepared in various forms (e.g., powder, film, fiber, gel, nanoparticles, porous structures; Fig. 1). Electrospun chitosan nanofibers exhibit small diameters, high surface area, tunable pore size, and porosity, enhancing bacterial contact and adsorption while effectively loading diverse antibacterial agents. Combined high crystallinity and size effects also improve mechanical properties, enabling applications in food packaging, biomedicine, tissue engineering, drug delivery, and air/water purification.

Fig. 2: Antibacterial mechanisms of chitosan.

As nature’s only positively charged biomacromolecule, chitosan’s protonated amino groups strongly adsorb negatively charged harmful substances, with antibacterial activity dependent on positive charge density. Its mechanisms include disrupting bacterial cell walls, inhibiting mRNA/protein synthesis, and metal ion chelation (Fig. 2). At pH < 6, protonated C-2 amino groups interact with bacterial cells, compromising wall integrity, attaching to DNA, and inhibiting replication. Antifungal effects include suppressing spore germination and hyphal growth.

Fig. 3: Synergistic antibacterial effects of chitosan with organic/inorganic agents.

Synergistic effects with organic/inorganic antibacterial agents (Fig. 3) significantly enhance performance: combining multiple mechanisms reduces resistance risks, improves stability, and prolongs activity. Blending chitosan with organic agents improves solubility/dispersibility, while inorganic agents enhance mechanical/barrier properties. Together, they overcome individual limitations for高效, safe, and durable antibacterial effects.

Table 1: Potential future prospects of chitosan-based nanofibers.

Chitosan-based nanofibers show broad prospects in biomedicine (wound dressings, tissue scaffolds, drug delivery), food packaging (active materials, coatings), environmental protection (water filtration, pollutant adsorption), personal care (antimicrobial wipes), and functional textiles (Fig. 1). Future innovations will focus on multifunctionality, intelligence, and sustainability.

Paper link: https://doi.org/10.1016/j.cej.2025.163776