Persistent microbial infection and decreased neovascularization are common issues associated with diabetic wound treatment. Hydrogel dressings that offer intrinsic antibacterial and angiogenesis-inducing may substantially avoid the use of antibiotics or angiogenic agents. Herein, a versatile hydrogel is fabricated using an amyloid-derived toxin simulant (Fmoc-LFKFFK-NH 2 , FLN) as building blocks, inspired by the defense strategy of Staphylococcus aureus (S. aureus). The simulant assemblies of the hydrogel function as both matrix components and functional elements for diabetic wound treatment. The hydrogel undergoes quick assembly from random monomers to nanofibrils with abundant b-sheet driven by multiple non-covalent interactions. The developed hydrogel demonstrates excellent biocompatibility and accelerates angiogenesis via hypoxia-inducible factor 1α (HIF-1α) and vascular endothelial growth factor A (VEGFA) signaling as a consequence of its amyloidal structure. The simulant-based nanofibrils endow the hydrogel with broad-spectrum antibacterial activity dominated by a membrane-disruption mechanism. In addition, the hydrogel exhibits excellent performance compared with the commercial hydrogel Prontosan in accelerating wound healing of diabetic mice infected with methicillinresistant S. aureus (MRSA). This study highlights the fabrication of a single component and versatile hydrogel platform, thereby avoiding the drugrelated side effects and complicated preparations and demonstrating its profound potential as a clinical dressing for the manage ment of microbeinfected diabetic wounds.

This article introduced a reversibly pH-responsive and targeting nanocarrier based on mesoporous silica nanoparticles which could be utilized to reduce the “secondary” side effects on normal tissues.

A mixture of multiple ingredients is often more effective than the individual ingredients. The functions of Lycium barbarum polysaccharide (LBP) glycoconjugate and grape seed procyanidins (GSP) are widely known. Here, we investigated the synergistic immune‐enhancing activity of LBP and GSP. Atomic force microscopy results suggested that the mixture of LBP and GSP exhibited circular structure unlike LBP alone, and the addition of polyphenols may change the spatial conformation of the sugar chain. The changes in the structure were related to the synergistic effect of the two functional agents on immune recovery. In vitro, the proliferation rate of splenocytes was higher in LBP + GSP group (64.16%), rather than the sum of LBP group (13.01%) and GSP group (43.61%) individually used. This synergistical proliferation of splenocytes may be correlated to the increasing intracellular free calcium levels. Furthermore, the mixture significantly enhanced the immunity in vivo, as evident from the recovery of peripheral white blood cell counts in LBP + GSP group (18.535 × 109/L) to normal group levels (18.115 × 109/L) and higher B cell proliferation than normal group (P < 0.05). These results highlight the immune‐enhancing activity of the combination of LBP and GSP associated with the structural changes, which may facilitate the development of functional foods with fewer resources but enhanced activities. Practical Application The synergistic effects of LBP and GSP on immunomodulatory were better than the sum of the effects of the individual agents both in vitro and in vivo. Our results may provide a research‐based support for the development of related functional products and an insight into the production of food resources with a fewer but more effective functional agents for better results.

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Site-specific and covalent attachment is the most desirable immobilization strategy, but classic methods typically require genetic engineering or complicated material fabrication, resulting in operational complexity and difficulty. Herein, a novel site-specific and covalent immobilization strategy based on accurately selected immobilization sites on lipase was developed. Specifically, computer-aided structural analysis of functional groups on lipase revealed that lysine residues with free amino groups were far away from the catalytic pocket and lid, which were suitable to be chosen as the best immobilization sites to effectively reduce the loss in its activity. Meanwhile, natural polyphenol-modified magnetic nanoparticles could increase the active immobilization sites, and lipase can be immobilized on them directly via a covalent reaction. This site-specific immobilization system exhibited significant enhancement in activity recovery (71.3%) compared to random immobilization (42.5 and 55.9%). As expected, experimental and computational analyses revealed that tailor-made site-specific immobilization carriers were beneficial to maintain the native catalytic pocket conformation and enhance the rigidity of the immobilized lipase, which exhibited a higher biodiesel yield (92.1%) than free and randomly immobilized lipases. Besides, the site-specifically immobilized lipase could maintain as high as 75.3% biodiesel yield after eight cycles, making it an ideal nanocatalyst for efficient production of biodiesel. Overall, the site-specific enzyme immobilization technology can provide stable catalytic activity advantages over the randomly covalent immobilization strategy, which can significantly promote green manufacturing and sustainable production.

Pre-existing tumor hypoxia and oxygen consumption by photodynamic therapy (PDT) always generate an inadequate oxygen supply, which often contributes to other therapy resistance, especially for aerobic treatments such as chemotherapy. In order to overcome this problem, we synthesized a chitosan (CS)-capped pH-/NIR-dual responsive and perfluorocarbon-based oxygen self-enriching photodynamic therapy nanosystem which could codeliver oxygen, photosensitizer, and chemotherapeutic drug. Simultaneously, in vitro results revealed that DOX release was stimulated by the acidic pH value with CS as a pH-responsive layer and rising temperature caused by the photothermal effect with an 808 nm laser, which could effectively reduce the nonspecific toxicity caused by premature drug release. Furthermore, due to the higher oxygen-carrying capability of perfluorocarbon, the decreased expression of the hypoxia-inducible factor-1α (HIF-1α) of tumors, as well as the significantly intense photodynamic effect and longer singlet ( 1 O 2 ) lifetime of the loaded photosensitizer, the elevated cytotoxicity was improved. More importantly, both in vitro and in vivo results showed that drug-loaded nanoparticles with oxygen-abundant properties achieved a similar anticancer therapy in both normoxic and hypoxic conditions against the difficulty led by deficient oxygen, as well as a good cellular internalization. Summarily, all these results pointed out that such a pH-/NIR-dual responsive drug carrier could enhance the synergetic anticancer therapy of chemotherapy and PDT by alleviation of tumor hypoxia, which provided a tempting controllable and multifunctional therapeutic application.

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