Abstract:

Objective Using raw cotton fabrics as medical cotton dressings in wound treatment cannot effectively prevent wound infection. Cotton dressings with antibacterial function can effectively prevent wound infections, but most of the antibacterial agents used for antibacterial finishing on cotton fabric face issues of resistance and high toxicity. In order to enhance the value of medical cotton-based dressings by ensuring safe and effective disinfection of wounds on wound management, a safe and low toxicity preparation strategy is urgently needed to endow cotton materials with excellent bactericidal ability.

Method Iodophor has been widely used for wound disinfection because of its good bactericidal effect and biocompatibility. However, few studies focused on the release of I₂ from cotton materials to prevent wound infections, mainly due to the low chelation strength of cotton materials to I₂, making it difficult to ensure sufficient I₂ release. In order to provide safe antibacterial effects to ordinary cotton materials, we selected less toxic I₂ as the antibacterial active ingredient. Cotton fabrics were coated with good biocompatibility of sodium carboxymethyl cellulose (CMC)/polyvinyl pyrrolidone (PVP) hybrid polymer, adding coated cotton fabrics into potassium iodide (KI) solution until full adsorption and sufficient swelling of the cotton fabrics. After that, hydrogen peroxide with a concentration of 3% was added to oxidized KI into I₂. Finally, through impregnation method, complexed I₂ molecules were attached onto the surface of the coated cotton fabric.

Results Both CMC and PVP are hydrophilic polymers, and the cotton fabric coated with CMC/PVP hybrid polymer still showed good water absorption ability and were able to adsorb I₂ up to 18.6 μg/mg, the existence of polyvinyl pyrrolidone made cotton fabric demonstrated a strong I₂ adsorption, ensured bactericidal effect against bacteria. Owing to the excellent film-forming properties of sodium carboxymethyl cellulose (CMC), cotton fabrics coated with CMC/PVP polymers formed a smooth surface, and the PVP polymer on the surface of cotton fabrics adsorbed a large amount of I₂. The inhibition zones test confirmed that cotton fabric complexing with I₂ was able to continuously release I₂ to form an antibacterial ring. Owing to the strong oxidation ability of I₂, cotton fabric complexing with I₂ was able to quickly kill bacteria in contact via destroying bacteria cell membrane. Cyto-toxicity experiments confirmed that all cotton fabrics, whether before or after coating and complexing with I₂, exhibited low toxicity against fibroblasts, and the cell survival rate of all samples was above 90%. When cotton fabric was used for bacterial infection wound treatment, the released I₂ killed 99.9% of bacteria at the wound tissue, significantly accelerating wound healing speed. In addition, the release of iodine ions effectively reduced the inflammatory response caused by bacterial infections, thereby accelerating wound healing.

Conclusion Finishing cotton fabric with CMC/PVP hybrid polymer coating is proven to maintain good water absorption performance and increase the chelating cap ability of cotton fabric to I₂, and after complexing with I₂ molecules, cotton fabric has almost no toxic effect on cellular tissues. Owing to the adsorption of full dose I₂, when using cotton fabrics complexing with I₂ for wound infected with bacteria, this cotton fabric can slowly release I₂ to kill bacteria at the wound tissues. In summary, using this cotton fabrics releasing I₂ can not only prevent wound infections but also reduce the inflammatory response caused by bacterial contamination, thereby accelerating wound healing. This cotton fabric as a medical dressing to treat wounds can effectively prevent wound infection without the need for disinfection. Therefore, this cotton fabric dressing can be a good substitute for current wound dressings and has great potential in the clinical treatment of wound infections.

Key words: cotton fabric, functional textile, antibacterial performance, medical dressing, coating modification, biocompatibility