Efficient wound healing by antibacterial property: Advances and trends of hydrogels, hydrogel-metal NP composites and photothermal therapy platforms

Bacterial infection is one of the biggest challenges in wound healing and imposes enormous burden on patient and medical system. Moreover, multidrug resistant microorganisms (MDR) limit the usage of therapeutic agents including antibiotics for wound treatment. Hydrogels are three-dimensional networks that have emerged as efficient scaffolds for the treatment of infected wounds. In addition to their intrinsic antibacterial activities, hydrogels are able to load and release therapeutic agents to keep the efficient dose during wound healing process. At the same lines, incorporation of metal nanoparticles (NPs) into hydrogels boosts their antibacterial activity. Moreover, photothermal agents embedded–hydrogel systems induce a hyperthermia effect under laser irradiation leading to a high therapeutic efficacy and wound healing property. In this review, designing, synthesis, physicochemical and biological properties of different types of antibacterial hydrogels as well as their applications in wound healing are discussed. Antibacterial hydrogel/NPs composites with emphasis on silver (Ag), gold (Au) and metal oxide NPs are also reviewed, along with photothermal therapy (PTT) using inorganic and organic photo thermal agents embedded–hydrogel systems. This review provides a perspective on background, prominence, obstacles and directions for the future applications of hydrogels and their hybrids in wound healing.