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The development of facile tailoring approach to adjust the intrinsic activity and stability of atomically-precise metal nanoclusters catalysts is of great interest but remians challenging. Herein, the well-defined Au8 nanoclusters modified by single-atom sites are rationally synthesized via a co-eletropolymerization strategy, in which uniformly dispersed metal nanocluster and single-atom co-entrenched on the poly-carbazole matrix. Systematic characterization and theoretical modeling reveal that functionalizing single-atoms enable altering the electronic structures of Au8 clusters, which amplifies their electrocatalytic reduction of CO2 to CO activity by ~18.07 fold compared to isolated Au8 metal clusters. The rearrangements of the electronic structure not only strengthen the adsorption of the key intermediates *COOH, but also establish a favorable reaction pathway for the CO2 reduction reaction. Moreover, this strategy fixing nanoclusters and single-atoms on cross-linked polymer networks efficiently deduce the performance deactivation caused by agglomeration during the catalytic process. This work contribute to explore the intrinsic activity and stability improvement of metal clusters.Tailoring catalytic performance of atomically-precise metal nanoclusters catalysts is of great interest but remains challenging. Here, the authors report a co-eletropolymerization strategy to modify well-defined Au8 nanoclusters by single-atom sites to enhance its electrocatalytic activity for the reduction of CO2 towards CO. [ABSTRACT FROM AUTHOR]

Low antibiotic utilization and inability to achieve real‐time monitoring of pathological status and treatment processes often result in unsatisfactory performance against bacterial infection. Developing a targeting antibacterial nanoprobe combining imaging with stimulus‐response antibiotic release is a promising strategy to precisely recognize lesions and enhance therapeutic efficacy for bacterial infection. In this work, we report a pH‐responsive theragnostic nanoplatform for targeted imaging and local drug release at the bacterial infection site. The nanoplatform consists of the core‐shell structure with persistent luminescence nanoparticles (PLNPs) as the core for autofluorescence‐free luminescence imaging and zeolitic imidazolate framework‐8 (ZIF‐8) as the shell to act as a carrier for antibiotics cefazolin. The core‐shell nanostructure is further conjugated with folic acid to facilitate the uptake and accumulation of the nanoparticles, and realize the autofluorescence‐free targeted imaging of the infection site. The acidic microenvironment at the bacterial infection site enables ZIF‐8 to decompose for specific drug release improve the performance in bacterial infection treatment. The developed pH‐responsive nanotheranostic probe is promising for autofluorescence‐free targeted imaging and therapy of bacterial infection. [ABSTRACT FROM AUTHOR]

Lanthanide metal–organic framework (Ln-MOF) based phosphors for light-emitting diodes (LEDs) play an important role in the fields of solid-state lighting and display. The rational design of organic antennae to address the drawback of low extinction coefficients of the lanthanide ions is highly desired. In this work, we provide a new design strategy to achieve an energy transfer molecule with a through-space conjugated folded structure, which can strengthen the skeleton rigidity and facilitate triplet state energy transfer. Consequently, one U-type π-conjugated molecule 2,6-bis(3,5-dicarboxylphenoxy) pyridine (H4L) was selected as a light gatherer to sensitize lanthanide ions for the construction of Ln-MOFs [Ln(HL)(H2O)3]n (Eu-MOF and Tb-MOF), which exhibit a long-lived luminescence lifetime (0.88 ms for Eu-MOF and 1.31 ms for Tb-MOF) and high quantum yields (50.87% for Eu-MOF and 85.64% for Tb-MOF). Furthermore, a white LED device with a colour rendering index (89) was fabricated using the mixture of Ln-MOFs with a commercial blue phosphor. [ABSTRACT FROM AUTHOR]

Macrophages are highly heterogeneous and exhibit a diversity of functions and phenotypes. They can be divided into pro‐inflammatory macrophages (M1) and anti‐inflammatory macrophages (M2). Diabetic wounds are characterized by a prolonged inflammatory phase and difficulty in healing due to the accumulation of pro‐inflammatory (M1) macrophages in the wound. Therefore, hydrogel dressings with macrophage heterogeneity regulation function hold great promise in promoting diabetic wound healing in clinical applications. However, the precise conversion of pro‐inflammatory M1 to anti‐inflammatory M2 macrophages by simple and biosafe approaches is still a great challenge. Here, an all‐natural hydrogel with the ability to regulate macrophage heterogeneity is developed to promote angiogenesis and diabetic wound healing. The protocatechuic aldehyde hybridized collagen‐based all‐natural hydrogel exhibits good bioadhesive and antibacterial properties as well as reactive oxygen species scavenging ability. More importantly, the hydrogel is able to convert M1 macrophages into M2 macrophages without the need for any additional ingredients or external intervention. This simple and safe immunomodulatory approach shows great application potential for shortening the inflammatory phase of diabetic wound repair and accelerating wound healing. [ABSTRACT FROM AUTHOR]

Infection microenvironment-mediated chemodynamic therapy (CDT) is an attractive way for the therapy of bacterial infection. However, therapeutic agents which can obtain real-time and in situ pathological information imaging signals during CDT are rare. Thus, it is an urgent need to explore antibacterial agents with both bacterial elimination and treatment process monitoring ability. Herein, we report an activatable antimicrobial nanoplatform with both ultralow-background persistent luminescent (PL) "turn-on" imaging and therapeutic capability. Chitosan (CS) is used as a linker to immobilize copper ions on the surface of persistent luminescent nanoparticles (PLNPs) to fabricate PLNPs–CS–Cu2+. The PL emission of PLNPs is quenched by Cu2+ under physiological conditions but recovered due to the conversion of Cu2+ into Cu+ by high glutathione (GSH) levels at the infection site. The produced Cu+ catalyzes H2O2 to generate hydroxyl radicals (•OH) for bacterial killing through oxidative stress. Also, the depletion of GSH amplifies the oxidative stress and enhances the therapy efficacy. The as-prepared antibacterial nanoplatform is promising for highly sensitive persistent luminescent imaging and simultaneous treatment of bacterial infection. [ABSTRACT FROM AUTHOR]