Wound-Healing Material with Antibacterial and Antioxidant Functions, Constructed Using Keratin, Hyperbranched Polymers, and MnO₂

Abstract

Wound healing, a global medical issue, poses a substantial financial burden. Therefore, developing low-cost and highly efficacious wound-healing materials is essential. In this study, we prepared keratin–hyperbranched polymer hydrogel-M (KHBP-M), a multifunctional composite gel, by mixing reduced keratin containing free sulfhydryl groups extracted from human hair waste, hyperbranched polymer (HBP) with double bonds at the end, and MnO2 nanoparticles prepared using the biological template method. Keratin has intrinsic wound-healing properties, and MnO2 is a wound-healing material with both photothermal antibacterial and reactive oxygen species (ROS)–scavenging abilities. KHBP-M showed antibacterial effects against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. When exposed to irradiation (808 nm), the killing ratio for S. aureus reached 99.99%, which is especially suitable for wound environments. A similar trend was noted for E. coli. The composite hydrogel also showed excellent ROS-scavenging ability and could resist oxidative stress in L929 cells. Furthermore, in an animal model of infected wounds, the KHBP-M hydrogel treated with near-infrared light had the fastest wound-healing rate, reaching 82.98% on day 15. Our study provides a promising wound-healing material, with simple preparation methods, easy access to sources, and low cost involved.

Self-Healable and Injectable Nanocomposite Hydrogel Loading Iron-Doped Carbon Dots for Synergistic Antibacterial Peptide-Photothermal-Photodynamic Antibacterial Therapy

“…Photothermal therapy (PTT) utilizes the photothermal conversion effect of photothermal agents to generate thermal energy under external light irradiation, increasing the surrounding temperature to kill bacteria. Photothermal agents can locally increase the temperature (above 50 °C) under laser irradiation, leading to protein overheating and denaturation, nucleic acid degradation, and cell membrane damage. − This physical therapy method has enormous natural advantages in dealing with bacterial infections caused by drug-resistant strains. Photodynamic therapy (PDT) is employed to stimulate photosensitizers through light irradiation with specific wavelengths to produce a large number of reactive oxygen species (ROS), such as singlet oxygen, superoxide anion, hydroxyl radical, etc., which will cause oxidative damage to bacterial cell membranes, ribosomes, and DNA. − However, simple photothermal therapy still has certain limitations, such as the high temperature generated by high-power laser that may damage normal tissues, while low power may not be able to completely kill bacteria.…”