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.

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.

Peptide- and drug-protected gold nanoclusters (Au NCs) with atomic precision have attracted research attention in the last few years owing to their ultrasmall size (<2 nm), well-defined structures, tunable photoluminescence from the visible to near-infrared range, water solubility, and good biocompatibility. These features, combined with low toxicity and efficient renal clearance, make such Au NCs promising candidates for biomedical use, including diagnosis, therapy, and theranostic. The incorporation of peptides or drugs into Au NCs enhances the stability, targeting specificity, cellular uptake, and prolonged circulation, enabling precise modulation of biological responses. Despite notable advances in achieving atomic precision employing complex ligands such as peptides or drugs, the synthetic methods of this new class of NCs remain a challenge. Careful control of molar ratio (Au: peptide/drug), reducing agent, temperature, and reaction time is required, because these factors directly influence the cluster size, optical properties, and in vivo performance. In this review, we highlight different synthetic approaches of atomically precise peptide- and drug-protected Au NCs, emphasizing the role of rational ligand design and reaction conditions, as well as the challenges associated with structural determination. We further discuss the optical and photoluminescence properties of peptide-protected Au NCs—the mostly explored features for biomedical applications. Finally, we conclude by outlining the current challenges, opportunities for scale-up synthesis, and future design perspectives for these emerging nanomaterials.

Atomically precise silver nanoclusters (AgNCs) offer unique opportunities to correlate structure and photophysical properties, yet enhancing their photoluminescence emission remains challenging due to dominance of non-radiative decay pathways. Here, we report a ligand-engineering strategy to modulate the optical properties of high-nuclearity Ag₅₆ NCs. The synthesized two NCs, Ag₅₆S₁₂(^tBuS)₂₀(CF₃CO₂)₁₂(MeCN)₃ (NC-I) and Ag₅₆S₁₂(^tBuS)₂₀(ⁿBuSO₃)₁₂ (NC-II), possess a similar hexagonal-close-packed Ag₁₄ kernel, which is encapsulated by a similar icosahedral S₁₂ middle-shell and an outer Ag₄₂ shell, but differ in overall symmetry and outer Ag-ligand shell connectivity. Replacement of bidentate CF₃CO₂⁻ with tridentate ⁿBuSO₃⁻ ligands increases overall Ag─X (X = O, S, and Ag) bonding interactions, resulting in not only a more rigid and compact outer Ag₄₂ shell structure but also contraction of cationic Ag₁₄ core and anionic icosahedral S₁₂ middle-shell. These structural modifications enhance radiative decay and suppress non-radiative pathways, leading to a 17-fold increase in photoluminescence quantum yield and extended average emission lifetime. Computational analysis confirms that ligand-induced geometric stabilization and electronic delocalization govern the excited-state dynamics. This work demonstrates that rational ligand design can synergistically tune cluster geometry, rigidity, and electronic structure, providing a general strategy to improve the photophysical performance of high-nuclearity AgNCs.

Nanozymes, a promising class of enzyme mimics based on nanostructures, have attracted considerable research interest. However, in sharp contrast to the structural precision of natural enzymes, most nanozymes are poorly defined structurally. The absence of nanozyme systems that mimic natural isoenzymes—which catalyze similar reactions despite slight differences in their chemical structures—has particularly hindered the understanding of their structure–performance relationships. Such nanozyme analogues, termed iso-nanozymes, remain largely unexplored. Here, we report the first pair of iso-nanozymes. Two analogous copper nanoclusters—[Cu₃₂(SC₂H₅)₁₆(PPh₃)₈Cl₉]⁺ (Cu₃₂) and [Cu₃₀(SC₂H₅)₁₆(PPh₃)₆Cl₉]⁺ (Cu₃₀)—were synthesized and structurally characterized. Single-crystal X-ray diffraction analysis reveals that Cu₃₀ possesses an identical metal framework and ligand types as Cu₃₂, with a comparable ligand distribution. The only structural difference is the absence of two PPh₃Cu⁺ units in Cu₃₀, which results in a substantial enhancement of its catalytic performance in the horseradish peroxidase-mimicking reaction. Under identical conditions, the specific activity (SA) of the Cu₃₀ nanozyme is approximately 6.5 times higher than that of Cu₃₂. Density functional theory calculations indicate that the notable difference in the SA between the two cluster nanozymes is attributed to variations in adsorption energies, which stem from their different geometric and electronic structures. This study not only introduces the novel concept of iso-nanozymes using atomically precise metal nanoclusters, but also establishes a model system for investigating the critical influence of nanozyme structure, down to the atomic level, on catalytic efficiency. These findings are anticipated to inspire further research interest in atomically precise metal nanoclusters within the nanozyme community.

The electrochemical reduction of CO₂, as a renewable energy-driven electrochemical system, has emerged as an environmentally benign approach for producing valuable chemicals and fuels under mild reaction conditions. Recent advances in the precise synthesis of metal nanoclusters, coupled with state-of-the-art characterization techniques, have enabled atomic-level investigation of structure–activity relationships in nanocatalysts. Due to their well-defined atomic architectures, the active metal sites within these nanocatalysts can be accurately identified, facilitating systematic studies on how compositions (structures) modulate catalytic performance. This review begins by summarizing recent advances in the controlled synthesis of atomically precise metal nanoclusters, followed by an overview of progress in the electrochemical reduction of CO₂ to CO using nanoclusters as catalysts. Subsequently, we systematically investigate the effects of metal kernel characteristics and staple properties on catalytic activity, selectivity, and stability. Furthermore, current challenges are outlined, and prospective research directions are proposed in this rapidly evolving field. It is anticipated that this review will inspire further innovation in the synthesis of atomically precise nanocluster catalysts, promote a deeper mechanistic understanding of metal nanocluster-mediated electrochemical CO₂ reduction, and push forward the related industrial applications.

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.

Like-charge pairing is a physical manifestation of the unique solvation properties of certain ion pairs in water. Water's high dielectric constant and related charge screening capability significantly influence the interaction between like-charged ions, with the possibility to transform it—in exceptional cases when noncovalent interactions are involved—from repulsion to attraction. Guanidinium cations (Gdm⁺) represent a quintessential example of such like-charge pairing due to their specific geometry and electronic structure. In this work, we present experimental validation and quantification of Gdm⁺-Gdm⁺ contact ion pairing in water utilizing nuclear magnetic resonance (NMR) spectroscopy complemented by molecular dynamics (MD) simulations and density functional theory (DFT) calculations. The observed Gdm⁺–Gdm⁺ interaction is attractive albeit weak—about −0.5 kJ·mol⁻¹ —which aligns with theoretical estimation from MD simulations. We contrast the behavior of Gdm⁺ with that of NH₄⁺ cations, which exhibit no contact ion pairing in water. DFT calculations predict that the NMR chemical shift of Gdm⁺ dimers is different than that of monomers, in agreement with NMR titration curves that display a nonlinear Langmuir-like behavior. Additionally, we conducted cryo-electron microscopy—to our knowledge, for the first time—on concentrated oligoarginines R₉, which, unlike nona-lysines K₉, exhibit aggregation in water. These results point to like charge pairing of the guanidinium side chain groups, as corroborated also by MD simulations and free energy calculations.

Organic semiconductor lasers are attractive for low thresholds and cost, but triplet accumulation hampers their electrically pumped development. Compared to existing organic lasing materials, triplet-triplet annihilation (TTA) systems are capable of tolerating high triplet concentrations and may facilitate stable laser emission under electrical pumping. To avoid energy losses in doped multicomponent TTA systems, herein, we report an organic semiconductor lasing material BH001 with TTA properties, which combines concurrent triplet harvesting and lasing within a single molecular framework. Dislocations between π-conjugated planes reduce π-π stacking-induced fluorescence quenching, yielding high photoluminescence quantum yield (PLQY) in the crystal. The TTA process in BH001 can be observed through a color change from red to blue by the sensitization of PtOEP. Given that nanosecond/femtosecond transient absorption (ns-TA and fs-TA) spectroscopy has demonstrated the appreciable ability of BH001 to generate triplet states, TTA-delayed fluorescence of pure BH001 crystal was directly detected using a streak camera. A laser constructed from this TTA crystal achieved low-threshold blue emission at 440 nm (P_th = 15.4 µJ/cm²), which is increased in an oxygen atmosphere, suggesting the involvement of triplets. Upon excitation with nanosecond laser pulses that are more prone to cause triplet stacking, the BH001 crystal exhibits stimulated emission behavior. This study demonstrates a lasing molecule with TTA properties, highlighting its potential in continuous wave (CW) pumped and ultimately electrically pumped systems.

Protein aggregation drives proteinopathies ranging from ALS to systemic amyloidosis, yet the multiscale determinants bridging sequence, structure, and kinetics remain elusive. We present SKALE, an interpretable machine learning framework that integrates sequence motifs, AlphaFold-derived structural descriptors, and experimental kinetics to decode aggregation mechanisms. SKALE identifies latent hotspots that evade conventional tools and matches high-performing neural baselines while preserving computational efficiency. In ALS-linked SOD1 G86R, the model isolates a risk region at residues 72–91 where preserved β-sheet geometry coincides with weakened hydrogen bonding to drive nucleation. Similarly, analysis of TDP-43 S332N reveals that a locally unwound helix increases surface exposure, a prediction validated by showing that targeted deletion of model-identified regions significantly reduces cellular aggregation. The framework generalizes to Tau P301L and PRNP variants where it uncovers distal aggregation-prone regions to discriminate pathogenic drivers from neutral mutations. Interpretability analysis further disentangles global from mutation-local mechanisms to reveal that β-sheet propensity acts as a shared determinant while hydrogen bond dynamics define specific routes to nucleation. These findings establish SKALE as a scalable, disease-agnostic engine that combines high-fidelity prediction with biophysical resolution to decode the molecular logic of misfolding and guide therapeutic design.

Ionic phototheranostic agents have found extensive application in preclinical and clinical practice owing to their excellent biocompatibility and synergistic diagnostic–therapeutic integration. However, they still suffer from certain limitations, such as short absorption/emission wavelengths, poor photostability, aggregation-caused fluorescence self-quenching, and diminished phototherapeutic efficacy upon aggregation, which collectively hinder their efficacy in complex clinical scenarios. To address these challenges, a second near-infrared (NIR-II) ionic phototheranostic agent, namely DT-BT-BIn, is rationally designed and synthesized via an innovative dual-acceptor engineering strategy. DT-BT-BIn ingeniously integrates benzothiadiazole and benzo[c,d]indolium as dual-acceptor units, which successfully achieves superior aggregation-induced NIR-II emission characteristics, highly efficient Type I/II photodynamic activity coupled with photothermal effect, and excellent photostability. Moreover, the self-assembled DT-BT-BIn nanoprobes (NPs) can be effectively internalized by cancer cells in vitro. Under irradiation, DT-BT-BIn NPs are capable of disrupting mitochondrial membrane potential, thereby inducing apoptotic cell death. Furthermore, in vivo investigations demonstrate DT-BT-BIn NPs can effectively accumulate at tumor location, enabling NIR-II fluorescence/photothermal imaging-guided precise tumor ablation, while simultaneously maintaining favorable biosafety toward normal tissues. Collectively, this study underscores the considerable promise of the dual-acceptor strategy in constructing high-performance NIR-II ionic phototheranostic agents and provides a new avenue for clinical precision cancer phototherapy.

Solvents in crystalline materials typically exist either as structural components that stabilize the framework or as adsorbed guests that modulate properties, yet achieving their orthogonal coexistence within a single system remains challenging. This study proposes a natural mineral-inspired solvent hierarchy strategy that enables the concurrent achievement of framework stability and dynamic responsiveness in hydrogen-bonded organic frameworks (HOFs) through the orthogonal integration of structural and adsorbed solvents. We have validated the feasibility of this solvent hierarchy approach based on four model systems with progressively increasing stability and dynamism: (1) unstable HOFs containing only adsorbed solvents, (2) unstable HOFs with low-binding-energy structural solvents, (3) stable HOFs incorporating strong-fitted structural solvents, and (4) stable HOFs with structural solvents and dynamically adjustable adsorption solvents. Crystallographic and theoretical analyses reveal that the superior stability of structural solvents originates from the high-electron-density oxygen of the DMSO S═O bond, which acts as a strong hydrogen-bond acceptor, forming stable N─H···O═S bonds with amine groups. The host's aggregation-induced emission (AIE) characteristics allow real-time optical monitoring of reversible single-crystal-to-single-crystal transformations without compromising structural integrity, demonstrating promising applications for visual water content and water leakage detection. This work not only establishes a new paradigm in solvent engineering for developing smart crystalline materials but also expands the design possibilities for functional porous frameworks.

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.

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.

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.