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[Display omitted] • FeS nanoparticles were synthesized in situ in the GA hydrogels, yielding of FeS/GA hydrogels. • FeS/GA hydrogels induced bacterial death through the combination of ferroptosis damage and energy metabolism disruption. • FeS/GA hydrogels regulated macrophage responses in the inflammatory microenvironment. • FeS/GA hydrogels promoted the bacteria-infected diabetic wound healing in a simple, effective, and safe manner. Diabetic wound treatment faces great challenges in clinic. Staphylococcus aureus (S. aureus) is one of the most frequently isolated pathogens from the diabetic infections, which can severely impede wound healing time. Herein, ferrous sulfide (FeS) nanoparticles were fabricated through an in situ reaction between Fe2+ and S2− in glycyrrhizic acid (GA) solution. As the FeS nanoparticles aged, the solution gradually transformed into a gel, exhibiting excellent mechanical strength, injectability, and biocompatibility as a wound dressing. In addition to its own pharmacological effects, GA could act as the protector for FeS from oxidation of air. It also provided a weak acidic microenvironment, facilitating the pH-dependent dissolution reaction of FeS to release H 2 S and Fe2+. Notably, the effective antibacterial performance of the FeS/GA hydrogels towards S. aureus and multi-drug resistant S. aureus (MRSA) was achieved via the degradedly released Fe2+ and H 2 S through combination of ferroptosis damage and energy metabolism disruption. Moreover, FeS/GA hydrogels effectively modulated the proportion of M1/M2 macrophages, reduced the secretion of inflammatory cytokines, and significantly enhanced the proliferation and migration of fibroblasts in vitro. Importantly, in an MRSA-infected diabetic wound model, the FeS/GA hydrogels efficiently eradicated bacteria and regulated the inflammatory microenvironment, thereby promoting the diabetic wound repair. Overall, our study establishes a novel strategy for developing multifunctional hydrogels that serve as an effective therapeutic platform for managing bacteria-infected diabetic wounds. [ABSTRACT FROM AUTHOR]

A pH/NIR responsive and injectable hydrogel was constructed by combining three biocompatible components—CaCO3, polydopamine and sodium alginate—for local calcium ions interference therapy and photothermal therapy against melanoma. [Display omitted] Melanoma is an aggressive tumor located in skin with high rates of recurrence and metastasis. Due to the limited traditional therapies, the development of novel strategies against melanoma is urgently quested. To reduce the side effects of traditional administration ways and amplify the killing effect, an injectable sodium alginate (SA)-based hydrogels were developed, in which CaCO 3 /polydopamine nanoparticles (CaCO 3 /PDA NPs) were embedded for the synergistic photothermal/calcium ions interference therapy of melanoma. In the study, the formation conditions and mechanical properties of CaCO 3 /PDA-SA hydrogels were characterized, and their antitumor efficiency and mechanism against mouse melanoma cells were investigated. When injected intratumorally, CaCO 3 /PDA-SA fluid was converted into hydrogel in situ through the interaction of pH-sensitive released Ca2+ and alginate chains, which increased the retention time of photothermal agents (CaCO 3 /PDA NPs) at tumor sites and thereby was more conducive to produce hyperthermia via photothermal conversion to combat melanoma. Moreover, in acidic tumor microenvironment, the residual CaCO 3 /PDA NPs in hydrogels continuously decomposed and released Ca2+ to destroy the Ca2+ buffering capacity and evoke the mitochondrial Ca2+-overloading, resulting in the inhibition of adenosine triphosphate production to accelerate cell death. Notably, besides the heat elevation, the near-infrared light (NIR) irradiation would further enhance the release of Ca2+ to promote the Ca2+-involved cell death. Therefore, a pH/NIR-responsive and injectable SA-based hydrogels were successfully established and showed enhanced treatment efficacy of melanoma through the synergism of photothermal therapy and calcium ions interference therapy. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Fe-TiO 2-x /TiO 2 S-scheme homojunction was constructed. • The Fe-TiO 2-x /TiO 2 exhibits optimized CO/CH 4 generation rates of 122/22 μmol g-1h−1. • The role of OV and Fe in improving catalytic performance has been discussed. • The photocatalytic mechanism was detailedly analyzed. CO 2 -to-high value-added chemicals via a photocatalytic route is of interest but strangled by the low efficiency. Herein, a novel Fe-TiO 2-x /TiO 2 S-scheme homojunction was designed and constructed by using a facile surface modification approach whereby oxygen vacancy (OV) and Fe introducing on the TiO 2 nanorod surface. The as-synthesized Fe-TiO 2-x /TiO 2 S-scheme homojunction exhibits positive properties on promoting photocatalytic CO 2 reduction: i) the nanorod structure provides numerous active sites and a radical charge transfer path; ii) the doped Fe and OV not only synergistically enhance light utilization but also promote CO 2 adsorption; iii) the Fe-TiO 2-x /TiO 2 S-scheme homojunction benefits photoexcited charge separation and retains stronger redox capacity. Thanks to those good characters, the Fe-TiO 2-x /TiO 2 homojunction exhibits superior CO 2 reduction performances with optimized CO/CH 4 generation rates of 122/22 μmol g-1h−1 which exceed those of pure TiO 2 by more than 9.4/7.3 folds and most currently reported catalytic systems. This manuscript develops a facile and universal approach to synthesize well-defined homojunction and may inspire the construction of other more high-efficiency photocatalysts toward CO 2 reduction and beyond. [ABSTRACT FROM AUTHOR]