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Chemotherapy-induced oral mucositis (CIOM) is a prevalent complication of chemotherapy and significantly affects the treatment process. However, effective treatment for CIOM is lacking due to the unique environment of the oral cavity and the single effect of current drug delivery systems. In this present study, we propose an innovative approach by combining a methacrylate-modified human recombinant collagen III (rhCol3MA) hydrogel system with hyaluronic acid-epigallocatechin gallate (HA-E) and dopamine-modified methacrylate-alginate (AlgDA-MA). HA-E is used as an antioxidant and anti-inflammatory agent and synergizes with AlgDA-MA to improve the wet adhesion of hydrogel. The results of rhCol3MA/HA-E/AlgDA-MA (Col/HA-E/Alg) hydrogel demonstrate suitable physicochemical properties, excellent wet adhesive capacity, and biocompatibility. Notably, the hydrogel could promote macrophage polarization from M1 to M2 and redress human oral keratinocyte (HOK) inflammation by inhibiting NF-κB activation. Wound healing evaluations in vivodemonstrate that the Col/HA-E/Alg hydrogel exhibits a pro-repair effect by mitigating inflammatory imbalances, fostering early angiogenesis, and facilitating collagen repair. In summary, the Col/HA-E/Alg hydrogel could serve as a promising multifunctional dressing for the treatment of CIOM.

MnCeOx/TiO2has been widely used in selective catalytic reduction (SCR) of NOxat low temperature. However, it is often poisoned in the presence of water vapor and sulfur dioxide. In this work, the promotion mechanism of Ba modification was investigated. Results show that the doped BaO reacts with CeO2and forms BaCeO3. This unique perovskite structure of BaCeO3significantly enhances NO oxidation and NH3activation of MnCeOx/TiO2catalyst so that the NO conversion and the resistances to SO2improve. It is found that Ba species obviously promotes the NO adsorption ability and improve the redox properties of MnCeOx/TiO2catalyst. While the acid properties of the catalyst are inhibited by Ba modification and among which Lewis acid sites are dominant for both MnCeOx/TiO2and MnCe(Ba)Ox/TiO2catalysts. Furthermore, in situDRIFT experiments reveal that the NO reduction upon MnCeOx/TiO2and MnCe(Ba)Ox/TiO2catalysts follows both E-R and L-H mechanisms, in which L-H is preferred. Ba species enhances the formation of active nitrate species, which accelerates the NO reduction through L-H mechanism. It is interesting that although Ba species weakens the NH3adsorption, it induces the ammonia conversion to coordination ammonia, which in turn accelerates the catalytic reaction.