A cross-linked hydrogel of bismuth sulfide nanoparticles with excellent photothermal antibacterial and mechanical properties to combat bacterial infection and prompt wound healing

Wound healing has always faced major challenges. Severe bacterial infections can delay healing and even be life threatening. According to relevant statistics, 70% of amputations are caused by wound infections. It is estimated that by 2050, drug-resistant bacteria will threaten the lives of 10 million people every year and cause a total loss of about 100 trillion U.S. dollars to the global economy. Therefore, there is an urgent need to develop new and efficient wound dressings that can effectively treat wound infections and promote wound healing while avoiding bacterial resistance. In this study, bismuth sulfide nanoparticles (Bi2S3 NPs) with good photothermal effect were combined with sodium alginate/acrylamide hydrogels (PAAm/NaAlg hydrogels) to prepare nanocomposite adhesive hydrogels (Bi2S3 NPs hydrogels) with strong antibacterial activity and good biocompatibility. Bi2S3 NPs can effectively convert light energy into heat energy and produce a certain amount of reactive oxygen species (ROS) to denature bacterial proteins and destroy cell membranes. In vivo experiments showed that hydrogels have a certain adhesion ability and can effectively promote wound healing without using any growth factors. As far as we know, this is the first time that Bi2S3 NPs were combined with hydrogels to be applied in the antibacterial field, which is expected to provide exciting research directions for Bi2S3 and other nanomaterials, and promote researchers to design more suitable dressings for clinical transformation and medical care.