Gallic acid-grafted chitosan photothermal hydrogels functionalized with mineralized copper-sericin nanoparticles for MRSA-infected wound management

• Published in: Carbohydrate polymers 2025-03, Vol.352, p.123179, Article 123179
• Main Authors: Li, Lihua, Ren, Li, Zhao, Qiuhan, Xu, Ke, Wu, Qiushuang, Su, Qianru, Li, Xin, Lü, Xin, Wang, Li
• Format: Article
• Language: English
• Subjects: Copper ions; Cross-linking; Gallic acid-grafted chitosan; Intracellular ROS scavenging; Mineralization; Photothermal hydrogel
• ISSN: 0144-8617
• DOI: 10.1016/j.carbpol.2024.123179

The management of wounds infected with drug-resistant bacteria represents a significant challenge to public health globally. Nanotechnology-functionalized photothermal hydrogel with good thermal stability, biocompatibility and tissue adhesion exhibits great potential in treating these infected wounds. Herein, a novel photothermal hydrogel (mCS-Cu-Ser1) was prepared through in situ mineralization in the hydrogel networks and ion cross-linking driven by copper ions (∼3 mM). Self-assembling polyphosphate sericin nanoparticles (Ser NPs) formed by an ultrasound-assisted anti-solvent method were as mineralization templates and gallic acid-grafted chitosan (mCS) was prepared as the sole matrix. Grafting of polyphenols and cross-linking of copper ions endowed mCS-Cu-Ser1 with injectable, skin-adhesive and self-healing characteristics. Due to the nonradiative relaxation of Cu2+ electron-hole pairs of copper phosphate on the surface of Ser NPs and the molecular thermo-vibrational effect of the mCS-Cu complex, mCS-Cu-Ser1 rapidly warmed up to 50 °C within one minute under near-infrared (NIR) irradiation. Integrating such excellent photothermal properties with antimicrobial activity and intracellular reactive oxygen species scavenging from mCS, mCS-Cu-Ser1 + NIR effectively accelerated methicillin-resistant Staphylococcus aureus (MRSA) infected wound healing. This work develops a novel dressing for the treatment of MRSA-infected wounds and provides some reference for the preparation of multifunctional acid-free chitosan hydrogels. [Display omitted]