Injectable self-healing CuS nanoparticle complex hydrogels with antibacterial, anti-cancer, and wound healing properties

It is of significant importance to develop an injectable self-healing hydrogel system that can simultaneously deal with antibacterial treatment, tumor therapy and wound healing acceleration for biomedical fields. Herein, a system of CuS nanoparticle complex (CuS NC) hydrogels with multiple functions is firstly developed through incorporating polyethylene glycol (PEG)-functionalized CuS nanoparticles (CuS NPs) with surface amino groups into a 3D network of oxidized dextran (ODex) and PEG with amino end groups. The in situ formed CuS NC hydrogels display not only excellent self-healing and injectable abilities, but also good biocompatibility for biomedical application. The introduction of CuS NPs endows the hydrogels with outstanding photothermal/photodynamic performance under near-infrared laser irradiation, creating the capability to fully kill S.aureus and E.coli bacteria, and to inhibit tumor growth in a subcutaneous skin-tumor model. The CuS NC hydrogels maintain sustained release of Cu2+ and moist microenvironment, and thus effectively accelerate wound healing in vivo. This work illustrates a facile strategy to prepare injectable, multifunctional nanoparticle hybrid hydrogels which can be used severally or simultaneously for bacterial infection treating, skin wound healing and skin-tumor therapy.