Aggregate (Hoboken, N.J.)最新文献

Collagen fibrillogenesis underlies the structural and mechanical properties of the extracellular matrix in connective and other tissues, yet its molecular mechanism remains poorly understood. Here, we show that a europium(III) dipicolinate complex (EuDPA) acts as a luminescent reporter of collagen aggregation. We combine Raman microscopy, circularly polarized luminescence (CPL), and molecular dynamics (MD) simulations to study this process. While Raman imaging directly visualizes the EuDPA-enhanced fibrillar architecture, CPL reveals enantioselective EuDPA–collagen interactions that accompany the fibrillogenesis. MD simulations indicate the presence of stabilizing interactions between hydroxyproline residues and the dipicolinate ligand. The results pave the way to monitoring of protein aggregation in general, and are relevant to fibrotic pathologies and biomimetic materials design.

The design of zero-background fluorescent sensing materials with specific functionalities is of great significance. Here, a special Eu-MOF with nonfluorescent emission was designed and driven by H₂O-induced cascade reaction through modulating the number of hydroxyl groups in ligands to enhance the signal-to-noise ratio, sensitivity, and reaction speed toward triacetone triperoxide (TATP). It is found that only when the ligand was selected as 2,5-dihydroxyterephthalic acid (DHTA), and with the introduction of H₂O, the intramolecular hydrogen bond could be changed to a weaker intermolecular hydrogen bond, which would be interrupted and oxidized from the original enol structure to ketone, producing the fluorescence turn-on response toward TATP. The special Eu-MOF exhibited a high-performance sensing for TATP, with fast response (<1 s), low limit of detection (LOD, 36.1 nM), superior selectivity even in the presence of 28 kinds of interferents, including the very similar hydrogen peroxide, strong robustness, and a practical detecting ability of 5 pg airborne TATP particle. Furthermore, we validated the practical feasibility of the specific Eu-MOF by integrating a sensing chip into a portable detector, thereby confirming that this MOF exhibits considerable potential for trace-level TATP detection in real-world application scenarios. The present nonfluorescent MOF design strategy and the elaborate modulation of the conformation in MOF structure would provide a new pathway for the exploration of novel functional MOFs as well as high-performance sensing methodologies.

The exploration of solvent-driven reversible structural transformation in clusters is crucial for advanced stimulus-responsive optical applications and understanding of structure-property relationships. Herein, we report a solvent-driven reversible transformation between two copper(I) clusters: [Cu(totp)(CH₃CN)₃][Cu₂I₃(totp)(DPPPy)]·CH₃CN 1 and Cu₄I₄(DPPPy)₂·0.5CH₂Cl₂ 2 (totp = tri-o-tolylphosphine, DPPPy = 2-[diphenylphosphino]pyridine). X-ray radioluminescence and encryption applications were studied based on structure-dependent photophysical properties difference. The noncovalent interaction-mediated space charge transition between isolated ion units of 1 enables more efficient thermally activated delayed fluorescence by reverse intersystem crossing, accounting for structure-dependent luminescence. Notably, compared to 2, 1 exhibits a higher scintillation light yield of 14832 photons MeV⁻¹, exceeding that of the commercial scintillator Bi₄Ge₃O₁₂ (8000 photons MeV⁻¹), and a low X-ray detection limit of 22.49 nGy s⁻¹, far below the typical diagnostic dose (5.5 µGy s⁻¹). Furthermore, scintillating film fabricated by 1 achieves X-ray imaging with a high spatial resolution of 16 lp/mm. The reversible structural interconversion enables solvent-responsive luminescent switches, and thus, the dynamic encryption system capable of multistage decryption was developed. This work not only offers new insight into solvent-regulated clusters transformations but also provides a promising strategy for developing high-performance copper(I) clusters-based scintillators and stimulus-responsive optical devices.

The efficient electrocatalytic oxidation of glycerol (GLY) is one of the most promising routes for the valorization of GLY. Doping has emerged as a powerful strategy to tailor the electrocatalytic performance of silver nanoclusters (Ag NCs), yet the effects of doping mode (surface vs. core) and the interface environment (e.g., electrolyte concentration) on the electrocatalytic performance for Ag NCs toward GLY oxidation remain understood. In this work, surface-doped Ag₄M₂(SR)₈ and core-doped Ag₂₄M(SR)₁₈ (M = Ni, Pd, Pt; SR = SPhMe₂) NCs were synthesized for electrocatalytic GLY oxidation. The results revealed a strong dependence of selectivity on doping mode and electrolyte concentration: under low KOH concentration, Pd- and Pt-doped Ag₄M₂ NCs exhibited 100% selectivity toward oxalic acid (OA), whereas Pd- and Pt-doped Ag₂₄M NCs delivered >95% selectivity for formic acid (FA). In contrast, under high KOH concentration, Pd- and Pt-doped Ag₄M₂ NCs gave rise to >80% FA, while Pd- and Pt-doped Ag₂₄M NCs produced >45% FA. Mechanism studies indicated that Ni doping predominantly enhanced catalytic activity via lowering the activation barrier of the initial reaction step (GLY→glyceraldehyde), whereas Pd and Pt doping modulated selectivity through reducing the energy barrier of the selective branch step (glyceric acid→OA, OA→FA). High KOH concentration promoted the oxidation by increasing the electrochemical active surface area and facilitating electron transfer of Ag NCs. This study provides clear guidance for designing high-performance Ag-based electrocatalysts for biomass valorization.

Gold nanoclusters (AuNCs) are ultrasmall (<2 nm) aggregates of gold atoms that exhibit discrete electronic states, size-dependent photoluminescence, and exceptional biocompatibility, making them ideal candidates for theranostic applications. Their tunable surface chemistry enables targeted delivery, while strong near-infrared emission and environmental responsiveness allow for sensitive detection and deep-tissue imaging. Recent advances have revealed that controlled assembly of AuNCs into higher-order architectures—guided by biological scaffolds such as nucleic acids, peptides, and proteins—can markedly enhance their optical and electronic properties through aggregation-induced emission (AIE) and stabilization of surface ligands.

This review summarizes recent progress in the design and biomedical applications of AuNC assemblies generated using biomolecules as structure-directing scaffolds. Covalent and noncovalent interactions with biomolecules enable the formation of well-defined one-, two-, and three-dimensional structures with tunable morphologies and sizes. These assemblies display distinctive photophysical behaviors that have been exploited for biosensing, bioimaging, and therapeutic applications in both cellular and in vivo models. Compared with individual AuNCs, assembled systems offer improved uptake, prolonged circulation, and efficient clearance, while protecting labile cargos such as nucleic acids and proteins. Moreover, their ordered and defined architectures can be engineered for controlled drug release and synergistic photo- or radiotherapeutic effects.

Despite these advances, fundamental understanding of how structural organization governs photophysical responses remains limited. Elucidating parameters such as intercluster spacing and loading density will be essential for optimizing performance. Overall, biologically guided AuNC assemblies represent a powerful platform for multifunctional biosensing and therapy, bridging nanoscale design with biological function.

Organic room-temperature phosphorescence (RTP) materials are promising for bioimaging applications due to their tunable structures, excellent biocompatibility, and long-lived luminescence. However, the development of highly efficient organic RTP materials for aqueous systems remains challenging, as the organic phosphorescence is prone to being quenched by the dissolved oxygen in water. Herein, heteroaromatic carboxylic acids serve as ligand guests to construct a series of host-guest composites with nontoxic, dense EDTA-M (M = Ca, Mg, and Al) coordination polymer in water. These composites exhibit ultra-long pure RTP of guest molecules with phosphorescence quantum yield up to 53%, and lifetime up to 589.7 ms, due to the synergistic effect of dual-network structure: a coordinatively cross-linked network of EDTA-M, and a non-covalent bonded network formed by ligands and water molecules. The phosphorescence intensity is more than three times that of the composite with a single coordination network. Notably, the dual-network configuration can form a rigid and dense structure and block the intrusion of external H₂O and O₂ molecules to avoid phosphorescence quenching in water. As a result, the RTP of the composites remains unchanged after 1 month in water. Furthermore, the nanoparticles fabricated from composites and anionic surfactants can be successfully applied in in vivo imaging of mice for the stable RTP in water. This work provides a novel strategy for the development of high-performance RTP materials in aqueous systems.

Fluorescent RNA aptamers offer promising opportunities for next-generation biosensing but are often limited by low signal-to-background ratios and unstable folding kinetics. In this work, a label-free Förster resonance energy transfer (FRET)-enhanced fluorescent artificial RNA condensate (F-FARCON) is developed for small-molecule sensing, leveraging neutral molecular crowders (e.g., polyethylene glycol 8K), and RNA structural motifs to induce multivalent interactions and drive dynamic self-assembly. As a demonstration, a label-free FRET system is constructed by integrating a histamine-responsive RNA aptamer with thioflavin T (ThT) as the fluorescence donor, which increases the signal-to-noise ratio while reducing sequence complexity and production costs. Molecular crowders optimize the thermodynamic environment of RNA–ligand and RNA–RNA multivalent interactions, thereby improving folding stability, signal amplitude (dynamic range of up to ∼970-fold), and target affinity. The platform exhibits fast kinetics (<15 min), an adjustable detection range (0.1–200 and 5–1000 µM), and high sensitivity (limit of detection, 15.36 nM), with robust performance in complex biological matrices. The platform is further integrated into a freeze-dried paper-based portable device that enables dual-channel fluorescence readout for on-site rapid detection without sophisticated instrumentation. To further validate the modularity of F-FARCON beyond histamine, we reprogrammed the recognition module to target S-adenosyl-L-methionine (SAM), achieving nanomolar limits of detection. By linking crowding-guided assembly to hierarchical photophysical enhancement and analytical performance, the work delineates a generalizable aggregate-science route to versatile, low-cost, and field-deployable fluorescence sensing across food safety, environmental monitoring, and biomedical diagnostics.

Metal nanoclusters (MNCs), comprising several to hundreds of metal atoms, have attracted significant research interest owing to their distinctive physicochemical properties. Reticular frameworks (RFs) with ordered porous structures, including metal–organic frameworks (MOFs), covalent organic frameworks (COFs), hydrogen-bonded organic frameworks (HOFs), and supramolecular organic frameworks (SOFs), possess a variety of unique properties due to their high crystallinity, high porosity, large surface area, and adjustable structure. The integration of MNCs with RFs endows the resulting composites with desirable features (e.g., enhanced and tunable optical properties, improved catalytic and photophysical activities, selective molecular recognition), which facilitates a broad spectrum of biomedical applications and advancing the development of integrated theranostic nanoplatforms. This review summarizes recent advances in the synthesis and biomedical applications of various MNCs/RFs composites. We systematically categorize and evaluate key strategies for incorporating MNCs into four types of RFs (MOFs, COFs, HOFs, and SOFs) while discussing the advantages and limitations of each approach. The biomedical applications of these composites are comprehensively reviewed, encompassing biosensing, bioimaging, antitumor therapy, and antibacterial treatments. Finally, the review addresses current challenges and outlines future research directions, with the aim of guiding the rational design of novel MNCs/RFs composites, enabling precise control over their structures and functions toward advanced biomedical applications.

The inherent oxygen sensitivity of hydrogenases has limited their biomedical use. We report a hybrid peptide–nanocluster hydrogel that establishes a self-sustained anaerobic microenvironment, enabling hydrogenase-catalyzed hydrogen therapy under aerobic conditions. The Fmoc-KYF peptide network traps O₂ in hydrophobic pockets, while photoexcited silver nanoclusters rapidly scavenge residual oxygen, ensuring stable hydrogen evolution. In vitro, the generated hydrogen mitigates oxidative stress and inflammation. In diabetic mice, the light-activated system accelerates wound closure, promotes angiogenesis, and drives macrophage polarization toward a reparative phenotype. This study introduces a bioengineering strategy that integrates material design, enzyme catalysis, and photodynamics to overcome oxygen limitation and advance hydrogenase-based therapeutic applications.

The strong electron–phonon coupling in organic photovoltaic materials significantly impedes exciton transport and promotes charge recombination, thereby exerting a detrimental effect on the overall performance of organic solar cells (OSCs). Mitigating electron–phonon coupling is therefore essential for developing high-performance OSCs. In this work, we introduce two solid additives, 1-bromo-3-chloronaphthalene (BCN-1) and 1-chloro-3-bromonaphthalene (BCN-2), into the bulk heterojunction active layer to address this fundamental challenge. We demonstrate that BCN-2 effectively suppresses high-frequency lattice vibrations, which minimizes electron–phonon scattering and thereby promotes efficient and long-range exciton diffusion. As a result, the BCN-2 processed devices exhibit prolonged exciton lifetime and superior charge carrier mobility compared to the control devices. These synergistic improvements in photophysical properties such as charge transport, contribute to a remarkable power conversion efficiency of 19.72% in the PM6:L8-BO-based OSCs. This work underscores the suppression of electron–phonon coupling as a critical and general strategy for advancing the performance of organic photovoltaic devices.