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Metal nanoclusters (NCs), owing to their atomic precision and unique molecule-like properties, have gained widespread attention for applications ranging from catalysis to bioimaging. In recent years, proteins, with their hierarchical structures and diverse functionalities, have emerged as good candidates for functionalizing metal NCs, rendering metal NC-protein conjugates with combined and even synergistically enhanced properties featured by both components. In this Perspective, we explore key questions regarding why proteins serve as complementary partners for metal NCs, the methodologies available for conjugating proteins with metal NCs, and the characterization techniques necessary to elucidate the structures and interactions within this emerging bionano system. We also highlight the emerging applications of metal NC-protein conjugates in biomedicine, catalysis, and biosensing in which the hybrid conjugates demonstrate remarkable performance. Furthermore, key challenges hampering further development of metal NC-protein conjugates, which include understanding binding mechanisms, expanding the diversity of proteins used for conjugation, and exploiting the individual roles of metal NCs and proteins within the hybrid systems, are discussed. This Perspective aims to systemize current synthetic methodologies and design principles for metal NC-protein conjugates, adding to their acceptance in precision nanotechnology.

Plasmon resonance plays an important role in improving the detection of biomolecules, and it is one of the focuses of research to use metal plasmon resonance to achieve fluorescence enhancement and to improve detection sensitivity. However, the problems of nondynamic tuning and fluorescence quenching of metal plasmon resonance need to be solved. Graphene surface plasmon resonance can be dynamically controlled, and the graphene adsorption of fluorescent molecules can avoid fluorescence quenching and greatly improve the fluorescence emission intensity. The graphene-metal hybrid structure designed in this work can solve the above two problems well, and the plasmon resonance can improve the fluorescence emission efficiency of molecules on the surface of graphene and improve the sensitivity of biological detection. At the same time, graphene nanoribbons in our hybrid structure do not require patterning, which greatly lowers the threshold for graphene application in biosensing.

Microplastics (MPs) and pesticides are identified as two environmental pollutants. In the present study, we showed evidence of toxic effects on honey bees from chronic oral exposure to food containing difenoconazole alone (Dif) and in a binary mixture with polystyrene (PS)-MPs (Dif + PS). We observed a disrupted gut microbial community structure in bees after difenoconazole exposure, and the gut microbiota structure richness increased at the phylum and genus levels in Dif + PS group. Transcriptomic analysis revealed that difenoconazole exposure caused 98 differentially expressed genes (DEGs), while 41 DEGs were identified in Dif + PS group. PS-MPs seemed to mitigate oxidative damage and changes in the transcriptome profile in honey bees caused by difenoconazole to some extent. However, coexposure increased the disordered microbial community composition. Our study highlights the importance of investigating possible additive and synergic activities between stressors to comprehensively understand the effects of pollutants on pollinating insects.

Nanomaterials that engage in well-defined and tunable interactions with proteins are pivotal for the development of advanced applications. Achieving a precise molecular-level understanding of nano-bio interactions is essential for establishing these interactions. However, such an understanding remains challenging and elusive. Here, we identified stoichiometric interactions of water-soluble gold nanoparticles (Au NPs) with bovine serum albumin (BSA), unraveling their synergism in manipulating emission of nano-bio conjugates in the second near-infrared (NIR-II) regime. Using Au 25 ( p -MBS) 18 ( p -MBS = para -mercaptobenzenesulfonic acid) as paradigm particles, we achieved precise binding of Au NPs to BSA with definitive molar ratios of 1:1 and 2:1, which is unambiguously evidenced by high-resolution mass spectrometry and transmission electron microscopy. Molecular dynamics simulations identified well-defined binding sites, mediated by electrostatic interactions and hydrogen bonds between the p -MBS moieties on the Au 25 ( p -MBS) 18 surface and BSA. Particularly, positively charged residues on BSA were found to be pivotal. By careful control of the molar ratio of Au 25 ( p -MBS) 18 to BSA, atomically precise [Au 25 ( p -MBS) 18 ] x -BSA conjugates ( x = 1 or 2) could be formed. Through a comprehensive spectroscopy study, an electron transfer process and synergistic effect were manifested in the Au 25 ( p -MBS) 18 -BSA conjugates, leading to drastically enhanced emission in the NIR-II window. This work offers insights into the precise engineering of nanomaterial-protein interactions and opens new avenues for the development of next-generation nano-bio conjugates for nanotheranostics.

In our previous studies of metal nanoparticle growth, we have come to realize that the dynamic interplay between ligand passivation and metal deposition, as opposed to static facet control, is responsible for focused growth at a few active sites. In this work, we show that the same underlying principle could be applied to a very different system and explain the abnormal growth modes of liquid nanoparticles. In such a liquid active surface growth (LASG), the interplay between droplet expansion and simultaneous silica shell encapsulation gives rise to an active site of growth, which eventually becomes the long necks of nanobottles. For this synthetic control, the imbalance of the said interplay is the critical factor, as demonstrated by carefully designed control experiments. Thus, LASG provides a coherent mechanism that encompasses a wide range of liquid-derived nanostructures, including hollow nanospheres, asymmetric teardrops, and hollow nanobottles with an opening. By adapting nanosynthesis techniques from the solid to liquid realm, we believe that LASG would provide deeper insights and more sophisticated synthetic controls.

Two-dimensional van der Waals (vdW) layered materials not only are an intriguing fundamental scientific research platform but also provide various applications to multifunctional quantum devices in the field-effect transistors (FET) thanks to their excellent physical properties. However, a metal-semiconductor (MS) interface with a large Schottky barrier causes serious problems for unleashing their intrinsic potentials toward the advancements in high-performance devices. Here, we show that exfoliated vdW Dirac semimetallic PtTe 2 can be an excellent electrode for electrons in MoS 2 FETs. High-performance FET characteristics reaching the FET mobility of 85 cm 2 V -1 s -1 are observed with a negligibly small Schottky barrier height and large on-off current ratio over 10 8 , which is among the highest performances in reported electrodes for MoS 2 . Discussions are had on the reason that exfoliated PtTe 2 with Dirac states shows highly efficient electrode performances based on the comparisons with various other metal electrodes. The orbital hybrid effect between Dirac-semimetal PtTe 2 and MoS 2 was evidenced by the relative shift of Raman spectra peaks in the heterojunction, resulting in good ohmic contacts. These findings provide an important route to find high-performance electrodes for layered vdW materials and their related quantum devices.

We report the canonical properties of the Bose-Einstein condensation of polaritons in the weak coupling regime, seen previously in many low-temperature experiments, at room temperature in a GaAs/AlGaAs structure. These effects include a nonlinear energy shift of the polaritons, showing that they are not noninteracting photons, and dramatic line narrowing due to coherence, giving coherent emission with a spectral width of 0.24 meV at room temperature with no external stabilization. This opens up the possibility of room temperature nonlinear optical devices based on polariton condensation., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Developing high-quality monocrystalline graphene has been an area of compelling research focus in the field of two-dimensional materials. Overcoming growth cessation presents a significant challenge in advancing the production of monocrystalline graphene. Herein, methods for sustaining a steady and consistent growth driving force are investigated based on the single-crystal growth theory. Comparative analysis revealed that each dynamic regulation method significantly increased the size of graphene compared to samples grown under stable pressure conditions. The grain size of high-quality graphene was significantly increased from ∼400 μm to ∼3 mm. Moreover, experimental measurements and numerical simulations were employed to investigate the impact of ambient pressure on the temperature and flow field. By considering the influence of pressure on the boundary layer and reaction rate constant, the mechanism underlying the dynamic regulation of ambient pressure was elucidated. Ultimately, the crystal growth kinetics theory, initially formulated with considerations of undercooling Δ T and supersaturation S eff , was developed by inducing the individual parameter of ambient pressure P . Due to diameter expansion and mechanical property promotion, a bilayer graphene Fabry-Perot interference (1100 μm) sensor with a stable signal response (52 dB) and superior minimum detection pressure at 20 kHz (87 μPa/Hz 1/2 ) was prepared. This innovative approach to regulating ambient pressure during crystal growth enables monocrystalline graphene to possess superior structure and properties for future technologies and provides insights into the production of other two-dimensional materials.

Gold nanoclusters (AuNCs) are emerging as promising functional probes for bioapplications. However, because of rapid renal clearance, it is a challenge to tailor their biofate and improve their disease-targeting ability in vivo. Herein, we report an efficient strategy to tailor their organotropic actions by rationally designing AuNC assemblies. The nanocluster assembly is established based on the moderate electrostatic interaction or strong coordination between AuNCs, enabled by solely chitosan (CS) or the coadded chelating metal ions (e.g., Gd 3+ ). We show that AuNCs-CS is rapidly excreted into urine, while further coordination of Gd 3+ confers assemblies with liver and lung accumulation capabilities, dependent on Gd 3+ contents. The organotropic actions are unraveled to result from their tunable stability in vivo and binding capability to cells/proteins. We also demonstrate that lung-targeting assemblies can enable specific NIR-II luminescence imaging of lung orthotopic tumors, which cannot be realized by employing discrete AuNCs. We anticipate that these findings will offer insights into the design principles of metal nanocluster probes and related bioapplications.

Oxide-water interfaces host many chemical reactions in nature and industry. There, reaction free energies markedly differ from those of the bulk. While we can experimentally and theoretically measure these changes, we are often unable to address the fundamental question: what catalyzes these reactions? Recent studies suggest that surface and electrostatic contributions are an insufficient answer. The interface modulates chemistry in subtle ways. Revealing them is essential to understanding interfacial reactions, hence improving industrial processes. Here, we introduce a thermodynamic approach combined with cavitation free energy analysis to disentangle the driving forces at play. We find that water dictates chemistry via large variations of cavitation free energies across the interface. The resulting driving forces are both large enough to determine reaction output and highly tunable by adjusting interface composition, as showcased for silica-water interfaces. These findings shift the focus from common interpretations based on surface and electrostatics and open exciting perspectives for regulating interfacial chemistry.

Nonvolatile memristors offer a salient platform for artificial neural network (ANN), yet the integration of different function and algorithm blocks into one hardware system remains challenging. Here we demonstrate the brain-like synaptic (SOT-S) and neuronal (SOT-N) functions in the Bi 2 Te 3 /CrTe 2 heterostructure-based spin-orbit torque (SOT) device. The SOT-S unit exhibits highly linear and symmetrical long-term potentiation/depression process, resulting in a fast-training of the MNIST data set with the classification accuracy above 90%. Meanwhile, the Sigmoid-shape transition curve inherited in the SOT-N cell replaces the software-based activation function block, hence reducing the system complexity. On this basis, we employ a serial-connected, voltage-mode sensing ANN architecture to enhance the vector-matrix multiplication signal strength with low reading error of 0.61% while simplifying the peripheral circuitry. Furthermore, the trainable activation function of SOT-N enables the implementation of the Batch Normalization algorithm and activation operation within one clock cycle, which bring about improved on/off-chip training performance close to the ideal baseline.

A family of microporous titanium-containing metal-organic frameworks (denoted as M 2 Ti-CPCDC, M = Mn, Co, Ni) has been synthesized by using a bimetallic [M 2 Ti(μ 3 -O)(COO) 6 ] cluster and a tritopic carbazole-based organic ligand H 3 CPCDC. M 2 Ti-CPCDC are stable and display permanent porosity for N 2 and CO 2 uptake, ranking among the most porous titanium-based metal-organic frameworks. M 2 Ti-CPCDC crystals exhibit n-type semiconductor behavior. Further catalytic studies demonstrate that all M 2 Ti-CPCDC materials are applicable for triggering photo-oxidative reactions of amines in air. More specifically, amines with electron-donating groups afford the aldehydes as the main products, while amines bearing electron-withdrawing groups give rise to imines as the main product. Among them, Mn 2 Ti-CPCDC exhibit the best photocatalytic activity, with conversion of benzylamine up to 99% and selectivity of 99%. Mn 2 Ti-CPCDC could be recycled in at least three runs while retaining crystallinity and catalytic activity. The reaction mechanism indicates that photoinduced hole (h + ), superoxide radical anion (O 2 ·- ), and singlet oxygen ( 1 O 2 ) are the main active species involved in the photo-oxidation process.

Aqueous sodium-ion batteries (ASIBs) and aqueous ammonium-ion batteries (AAIBs) attract great attention due to their low cost, safety, and environmental friendliness, but the lack of suitable electrodes with competitive capacity and redox potential limits their practical applications. Herein, we report a porous organic polymer (POP) with multiple redox processes as anodes for ASIBs and AAIBs. This POP displays desired redox potential and shows high reversible capacity of more than 200 mAh g -1 in both ASIBs and AAIBs. Full cells configured by this POP anode also display excellent performance (about 80% and 60% capacity retention over 1000 cycles in ASIBs and AAIBs). In addition, the intercalation chemistry of inorganic NH 4 + with this POP is investigated, illustrating that the pyrazine sites in this POP are the redox centers to reversibly combine with NH 4 + . This work provides a promising and alternative anode for ASIBs and AAIBs and paves a new way for the development of novel organic materials for other aqueous battery systems.

Developing a bifunctional oxygen electrocatalyst is crucial to improve the reversibility and cycle life of a rechargeable zinc-air battery (RZAB). Here, transition metal phosphides (TMPs) with a leaf-like hierarchical structure and multiphase composition can be synthesized by the "alloying-dealloying-phosphating" strategy. The as-prepared P-NiCo(1:1) electrode takes advantage of its internal dense nanoholes and synergistic effects induced by NiCoP-containing polyphase to reveal multifunctional catalysis, such as OER and ORR. In combination of these advantages, P-NiCo(1:1) exhibits an extremely low OER overpotential of 220 mV at 10 mA cm -2 , a higher half-wave potential of 0.79 V for ORR, and a smaller potential difference (Δ E ) of 0.66 V. The liquid RZAB with P-NiCo(1:1) as a cathodic bifunctional catalyst delivers a higher open-circuit voltage (OCV), a larger power density of 175 mW cm -2 , and longer cycling life for more than 180 h. Even when applied in solid-state flexible RZABs, the lightweight module could start high-power devices. With theoretical confirmation, the major phase NiCoP of P-NiCo(1:1) is helpful to increase the density of states, regulate the d-band center, and decrease the energy barrier to 2.13 eV, which are significantly superior to those of Co 2 P and Ni 2 P. It is believable that the synthetic strategy and activity-promoting mechanism acquired from this research can offer a guide to designing a promising rechargeable zinc-air battery system.

Magnetoresistance effects are crucial for understanding the charge-spin transport as well as propelling the advancement of spintronic applications. Here, we report the coexistence of magnetic-moment-dependent (MD) and magnetic-field-driven (FD) unidirectional magnetoresistance (UMR) effects in CoFeB/InSb/CdTe heterostructures. The strong spin-orbital coupling of InSb and the matched impedance at the CoFeB/InSb interface warrant a distinct MD-UMR effect at room temperature, while the interaction between the in-plane magnetic field and the Rashba effect at the InSb/CdTe interface induces the marked FD-UMR signal that dominates the high-field region. Moreover, owning to different spin scattering mechanisms, these two types of non-reciprocal charge transports show opposite polarities with respect to the magnetic field direction, which further enables an effective phase modulation of the angular-dependent magnetoresistance. The demonstration of the tunable UMR response validates our CoFeB/InSb/CdTe system as a suitable integrated building block for multifunctional spintronic memory and sensor designs.

Arbuscular mycorrhizae (AM) symbiosis can enhance plant resistance to drought stress (DS). This study aimed to investigate the DS effects on lipids at different stages of symbiosis and to link lipid profiles to arbuscule dynamics in tomato roots colonized by AM fungi. DS increased mycorrhizal colonization and arbuscule abundance at an early stage but decreased them at a later stage, delayed arbuscule development, and accelerated arbuscule senescence at a later stage. DS decreased the contents of phospholipids (PLs) and saturated neutral lipids (NLs) at the early stage but increased the contents of saturated PLs and unsaturated NLs at the late stage. Specifically, DS inhibited AM-specific PL contents but increased AM-specific NL contents, which was supported by the expression of RAM 2, STR / STR 2. These data indicate the negative effect of DS on AM symbiosis and arbuscule dynamics with the effect size depending on the symbiosis stage, which highlights the importance of the symbiosis stage under abiotic stress.

For nanochemistry, precise manipulation of nanoscale structures and the accompanying chemical properties at atomic precision is one of the greatest challenges today. The scientific community strives to develop and design customized nanomaterials, while molecular interactions often serve as key tools or probes for this atomically precise undertaking. In this Perspective, metal nanoclusters, especially gold nanoclusters, serve as a good platform for understanding such nanoscale interactions. These nanoclusters often have a core size of about 2 nm, a defined number of core metal atoms, and protecting ligands with known crystal structure. The atomically precise structure of metal nanoclusters allows us to discuss how the molecular interactions facilitate the systematic modification and functionalization of nanoclusters from their inner core, through the ligand shell, to the external assembly. Interestingly, the atomic packing structure of the nanocluster core can be affected by forces on the surface. After discussing the core structure, we examine various atomic-level strategies to enhance their photoluminescent quantum yield and improve nanoclusters' catalytic performance. Beyond the single cluster level, various attractive or repulsive molecular interactions have been employed to engineer the self-assembly behavior and thus packing morphology of metal nanoclusters. The methodological and fundamental insights systemized in this review should be useful for customizing the cluster structure and assembly patterns at the atomic level., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Co-published by University of Science and Technology of China and American Chemical Society.)

Metal nanoclusters (NCs) hold great promise for expressing multipeak emission based on their well-defined total structure with diverse luminescent centers. Herein, we report the surface motif-dictated triple phosphorescence of Au NCs with dynamic color turning. The deprotonation-triggered isomerization of terminal thiouracils can evolve into a mutual transformation among their hierarchical motifs, thus serving a multipeak-emission expression with good tailoring. More importantly, the underlying electron transfer is thoroughly identified by excluding the radiative and nonradiative energy transfer, where electrons flow from the first phosphorescent state to the last two ones. The findings shed light on finely tailing motifs at the molecular level to motivate studies on customizable luminescence characteristics of metal NCs.

Emerging point-of-care testing methods are extremely beneficial for personalized assessments of trace element metabolism including selenium (Se). Given the lack of timely evaluation methods for well-received Se fortification, an electrochemical solution was developed based on the recently identified urinary selenosugar (Sel) as a marker. The Se content of crude urine was rapidly determined (∼5 min), and the square-wave voltammetric responses of a Se-selective probe (SeSE) composed of liquid metal amalgam demonstrated comparable performance (e.g., detection limit: 19 nM) to central lab benchtop equipment within the physiological range. Meanwhile, SeSE enabled total urinary Se detection via a mere one-step oxidation. Additionally, SeSE was utilized to jointly assess the apparent internalization and utilization rate of two typical nutrients, selenite and selenomethionine, in a rat nutrition model, demonstrating consistent results with those obtained by HPLC-MS and ICP-MS. Upon systematic standardization directed by Ramaley's theory, SeSE was integrated into a battery-operated portable kit (dubbed "SeEye") with a micro electrochemical drive and tablet PC console for one-stop service trials in a local commercial scenario. This study establishes (1) a nutritive value classifier in a low-cost consumer electronic format and (2) noninvasive diagnostic technology for Se supplementation.

Mechanofluorochromic materials are a type of "smart" material because of their adjustable fluorescent properties under external mechanical force, making them significant members of the materials family. However, as the fluorescent characteristics of these materials highly depend on their microstructures, the still insufficiently in-depth research linking molecular structures to light emission motivates researchers to explore the fluorescent properties of these materials under external stimuli. In this work, based on synthetic [AgS 4 ] microplates, we explore a fascinating mechanical-induced photoluminescent enhancement phenomenon. By applying mechanical force to solid-state [AgS 4 ] to damage the surface morphology, a significant enhancement in photoluminescence is observed. Moreover, the emitted intensity increases with the extent of damage, which can be attributed to alterations in crystallinity. This work provides valuable insights into the relationship among photoluminescence, crystallinity, and mechanical force, offering new strategies for designing luminescent devices.

Electronically excited-state problems represent a crucial research field in quantum chemistry, closely related to numerous practical applications in photophysics and photochemistry. The emerging of quantum computing provides a promising computational paradigm to solve the Schrödinger equation for predicting potential energy surfaces (PESs). Here, we present a deep neural network model to predict parameters of the quantum circuits within the framework of variational quantum deflation and subspace search variational quantum eigensolver, which are two popular excited-state algorithms to implement on a quantum computer. The new machine learning-assisted algorithm is employed to study the excited-state PESs of small molecules, achieving highly accurate predictions. We then apply this algorithm to study the excited-state properties of the ArF system, which is essential to a gas laser. Through this study, we believe that with future advancements in hardware capabilities, quantum computing could be harnessed to solve excited-state problems for a broad range of systems.

Diabetic foot ulcers (DFU) are chronic, refractory wounds caused by diabetic neuropathy, vascular disease, and bacterial infection, and have become one of the most serious and persistent complications of diabetes mellitus because of their high incidence and difficulty in healing. Its malignancy results from a complex microenvironment that includes a series of unfriendly physiological states secondary to hyperglycemia, such as recurrent infections, excessive oxidative stress, persistent inflammation, and ischemia and hypoxia. However, current common clinical treatments, such as antibiotic therapy, insulin therapy, surgical debridement, and conventional wound dressings all have drawbacks, and suboptimal outcomes exacerbate the financial and physical burdens of diabetic patients. Therefore, development of new, effective and affordable treatments for DFU represents a top priority to improve the quality of life of diabetic patients. In recent years, nanozymes-based diabetic wound therapy systems have been attracting extensive interest by integrating the unique advantages of nanomaterials and natural enzymes. Compared with natural enzymes, nanozymes possess more stable catalytic activity, lower production cost and greater maneuverability. Remarkably, many nanozymes possess multienzyme activities that can cascade multiple enzyme-catalyzed reactions simultaneously throughout the recovery process of DFU. Additionally, their favorable photothermal-acoustic properties can be exploited for further enhancement of the therapeutic effects. In this review we first describe the characteristic pathological microenvironment of DFU, then discuss the therapeutic mechanisms and applications of nanozymes in DFU healing, and finally, highlight the challenges and perspectives of nanozyme development for DFU treatment.

The adverse respiratory outcomes motivated by silica nanoparticles (SiNPs) exposure have received increasing attention. Herein, we aim to elucidate the interplay of diverse cell populations in the lungs and key contributors in triggering lung injuries caused by SiNPs. We conducted a subchronic respiratory exposure model of SiNPs via intratracheal instillation in Wistar rats, where rats were administered with 1.5, 3.0, or 6.0 mg/kg body weight SiNPs once a week for 12 times in total. We revealed that SiNPs caused pulmonary interstitial injury in rats by histopathological examination and pulmonary hydroxyproline determination. Further, a single-cell RNA-Seq via screening 10 457 cells in the rat lungs disclosed cell-specific responses to SiNPs and cell-to-cell interactions within the alveolar macrophages, epithelial cells, and fibroblasts from rat lungs. These disturbed responses were principally related to the dysregulation of protein homeostasis (proteostasis), accompanied by an inflammatory response in macrophages, cell death in epithelial, proliferation, and extracellular matrix deposition in fibroblast. These cell-specific responses may serve a synergistic role in the pathogenesis of pulmonary interstitial disease triggered by SiNPs. In particular, the analyses of gene interaction networks and gene-disease associations filtered out heat shock proteins (Hsps) family genes crucial to the observed pulmonary lesions caused by SiNPs. Of note, both GEO database analysis and our experiments' validation indicated that Hsps, especially Hspd1, may be a key contributor to pulmonary interstitial injury, possibly through triggering oxidative stress, immune response, and disrupting protein homeostasis. Taken together, our study provides insights into pulmonary toxic effects and underlying molecular mechanisms of SiNPs from a single-cell perspective., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Co-published by Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, and American Chemical Society.)

We have placed a van der Waals homostructure, formed by stacking three two-dimensional layers of WS 2 separated by insulating hBN, similar to a multiple-quantum well structure, inside a microcavity, which facilitates the formation of quasiparticles known as exciton-polaritons. The polaritons are a combination of light and matter, allowing laser emission to be enhanced by nonlinear scattering, as seen in prior polariton lasers. In the experiments reported here, we have observed laser emission with an ultralow threshold. The threshold was approximately 59 nW/μm 2 , with a lasing efficiency of 3.82%. These findings suggest a potential for efficient laser operations using such homostructures., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

We report that constructed Au nanoclusters (NCs) can afford amazing white emission synergistically dictated by the Au(0)-dominated core-state fluorescence and Au(I)-governed surface-state phosphorescence, with record-high absolute quantum yields of 42.1% and 53.6% in the aqueous solution and powder state, respectively. Moreover, the dynamic color tuning is achieved in a wide warm-to-cold white-light range (with the correlated color temperature varied from 3426 to 24 973 K) by elaborately manipulating the ratio of Au(0) to Au(I) species and thus the electron transfer rate from staple motif to metal kernel. This study not only exemplifies the successful integration of multiple luminescent centers into metal NCs to accomplish efficient white-light emission but also inspires a feasible pathway toward customizing the optical properties of metal NCs by regulating electron transfer kinetics.

Hepatitis B virus (HBV) infection remains a major global health concern, necessitating the development of sensitive and reliable diagnostic methods. In this study, we propose a novel approach to enhance the sensitivity of HBV DNA detection by leveraging a concentration imbalance-driven DNA circuit (CIDDC) as an operational amplifier, coupled with a hybridization-responsive DNA-templated silver nanocluster (DNA-AgNCs) nanoprobe named Q·C6-AgNCs. The CIDDC system effectively converts and amplifies the input HBV DNA into an enriched generic single-stranded DNA output, which subsequently triggers the fluorescence of the DNA-AgNCs reporter upon hybridization, generating a measurable signal for detection. By incorporating the DNA circuit, we not only achieved enhanced sensitivity with a lower detection limit of 0.11 nM but also demonstrated high specificity with single-base mismatch discriminability for HBV DNA detection. Additionally, this mix-and-detect assay format is simple, user-friendly, and isothermal. This innovative strategy holds promise for advancing molecular diagnostics and facilitating the effective management of HBV-related diseases., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

To meet the diverse needs of humans, smart cloth has become a potential research hotspot to replace traditional cloth. However, it is challenging to manufacture a flexible fabric with multiple functions. Here, we introduce a smart cloth based on liquid metal (LM) conductive fibers. Ga 2 O 3 nanoparticles are obtained through ultrasonic pretreatment. Furthermore, a coordination bond is formed between thiol groups on the surface of protein fibers and Ga 2 O 3 through a scraping method, allowing Ga 2 O 3 particles to be grafted onto the surface of protein fibers in situ. Finally, LM conductive fibers are encapsulated using a photocuring adhesive. In addition, a wearable smart cloth integrated with multiple sensors has been developed based on LM conductive fibers. Users can not only monitor their movement trajectory and the surrounding environment in real time but also have their data supervised by family members through a client, achieving remote and continuous monitoring. The development of this wearable smart cloth provides strong support for future wearable, flexible electronic devices.

The design of aqueous zinc-ion batteries (ZIBs) that have high specific capacity and long-term stability is essential for future large-scale energy storage systems. Cathode materials with extended π-conjugation and abundant active sites are desirable to enhance the charge storage performance and the cycling stability of the aqueous ZIB. Based on this concept, 6,9-dihydropyrazino[2,3- g ]quinoxaline-2,3,7,8(1 H ,4 H )-tetrone was chosen as the monomer to be electropolymerized onto carbon cloth (PDHPQ-Tetrone/CC). When used as the cathode material for aqueous ZIBs, an exceptional cycling life (>20,000 cycles) at a current density of 10 A g -1 was achieved, with the specific capacity maintained at 82.8% and with the Coulombic efficiency at around 100% throughout cycling. At the charge-discharge current density of 0.1 A g -1 , the ZIB with PDHPQ-Tetrone/CC achieved a high specific capacity of 248 mAh g -1 . Kinetic analyses showed that both surface-capacitive-controlled processes and semi-infinite diffusion-controlled processes contribute to the stored charge. The charge storage mechanism was investigated with ex situ characterizations and involves the redox processes of carbonyl/hydroxyl and amino/imino groups coupled with insertion and extraction of both Zn 2+ and H + .

20( S )-Protopanaxadiol (PPD) is one of the bioactive ingredients in ginseng and possesses neuroprotective properties. Brain-type creatine kinase (CK-BB) is an enzyme involved in brain energy homeostasis via the phosphocreatine-creatine kinase system. We previously identified PPD as directly bound to CK-BB and activated its activity in vitro . In this study, we explored the antidepressive effects of PPD that target CK-BB. First, we conducted time course studies on brain CK-BB, behaviors, and hippocampal structural plasticity responses to corticosterone (CORT) administration. Five weeks of CORT injection reduced CK-BB activity and protein levels and induced depression-like behaviors and hippocampal structural plasticity impairment. Next, a CK inhibitor and an adeno-associated virus-targeting CKB were used to diminish CK-BB activity or its expression in the brain. The loss of CK-BB in the brain led to depressive behaviors and morphological damage to spines in the hippocampus. Then, a polyclonal antibody against PPD was used to determine the distribution of PPD in the brain tissues. PPD was detected in the hippocampus and cortex and observed in astrocytes, neurons, and vascular endotheliocytes. Finally, different PPD doses were used in the chronic CORT-induced depression model. Treatment with a high dose of PPD significantly increased the activity and expression of CK-BB after long-term CORT injection. In addition, PPD alleviated the damage to depressive-like behaviors and structural plasticity induced by repeated CORT injection. Overall, our study revealed the critical role of CK-BB in mediating structural plasticity in CORT-induced depression and identified CK-BB as a therapeutic target for PPD, allowing us to treat stress-related mood disorders.

Natural enzymes intricately regulate substrate accessibility through specific amino acid sequences and folded structures at their active sites. Achieving such precise control over the microenvironment has proven to be challenging in nanocatalysis, especially in the realm of ligand-stabilized metal nanoparticles. Here, we use atomically precise metal nanoclusters (NCs) as model catalysts to demonstrate an effective ligand engineering strategy to control the local concentration of CO 2 on the surface of gold (Au) NCs during electrocatalytic CO 2 reduction reactions (CO 2 RR). The precise incorporation of two 2-thiouracil-5-carboxylic acid (TCA) ligands within the pocket-like cavity of [Au 25 ( p MBA) 18 ] - NCs ( p MBA = para -mercaptobenzoic acid) leads to a substantial acceleration in the reaction kinetics of CO 2 RR. This enhancement is attributed to a more favorable microenvironment in proximity to the active site for CO 2 , facilitated by supramolecular interactions between the nucleophilic N δ- of the pyrimidine ring of the TCA ligand and the electrophilic C δ+ of CO 2 . A comprehensive investigation employing absorption spectroscopy, mass spectrometry, isotopic labeling measurements, electrochemical analyses, and quantum chemical computation highlights the pivotal role of local CO 2 enrichment in enhancing the activity and selectivity of TCA-modified Au 25 NCs for CO 2 RR. Notably, a high Faradaic efficiency of 98.6% toward CO has been achieved. The surface engineering approach and catalytic fundamentals elucidated in this study provide a systematic foundation for the molecular-level design of metal-based electrocatalysts.

Metal nanoclusters (MNCs) represent a promising class of materials for catalytic carbon dioxide and proton reduction as well as dihydrogen oxidation. In such reactions, multiple proton-coupled electron transfer (PCET) processes are typically involved, and the current understanding of PCET mechanisms in MNCs has primarily focused on the sequential transfer mode. However, a concerted transfer pathway, i.e., concerted electron-proton transfer (CEPT), despite its potential for a higher catalytic rate and lower reaction barrier, still lacks comprehensive elucidation. Herein, we introduce an experimental paradigm to test the feasibility of the CEPT process in MNCs, by employing Au 18 (SR) 14 (SR denotes thiolate ligand), Au 22 (SR) 18 , and Au 25 (SR) 18 - as model clusters. Detailed investigations indicate that the photoinduced PCET reactions in the designed system proceed via an CEPT pathway. Furthermore, the rate constants of gold nanoclusters (AuNCs) have been found to be correlated with both the size of the cluster and the flexibility of the Au-S framework. This newly identified PCET behavior in AuNCs is prominently different from that observed in semiconductor quantum dots and plasmonic metal nanoparticles. Our findings are of crucial importance for unveiling the catalytic mechanisms of quantum-confined metal nanomaterials and for the future rational design of more efficient catalysts.

A robust, microporous, and photoactive aluminum-based metal-organic framework (Al-MOF, LCU-600) has been assembled by an in situ-formed [Al 3 O(CO 2 ) 6 ] trinuclear building unit and a tritopic carbazole ligand. LCU-600 shows a high water stability and permanent porosity for N 2 and CO 2 adsorption. Notably, the incorporation of photoresponsive carbazole moieties into LCU-600 makes it a highly efficient and recyclable photocatalyst for aerobic photo-oxidation of sulfides into sulfoxides under an air atmosphere at room temperature. Mechanism investigations unveil that photogenerated holes (h + ), superoxide radical anion (O 2 •- ), and singlet oxygen ( 1 O 2 ) are critical active spices for the photo-oxidation reaction performed in an air atmosphere.

As emerging contaminants in the environment, antibiotic resistance genes (ARGs) have aroused a global health crisis and posed a serious threat to ecological safety and human health. Thus, efficient and accurate onsite detection of ARGs is crucial for environmental surveillance. Here, we presented a colorimetric-photoelectrochemical (PEC) dual-mode bioassay for simultaneous detection of multiple ARGs by smartly incorporating rolling circle amplification (RCA) into a stimuli-responsive DNA nanoassembly, using the tetracycline resistance genes tetA and tetC as models. The tailored DNA nanoassembly containing RCA amplicons hybridized with specific signal probes: CuO nanoflowers-anchored signal DNA1 and HgO nanoparticles-anchored signal DNA2, respectively. Upon exposure to an acidic stimulus, numerous Cu 2+ and Hg 2+ were released, serving as the reporting agent of colorimetric/PEC dual-mode assay. The released Cu 2+ and Hg 2+ induced localized surface plasmon resonance shifts in Au nanorods and triangular Ag nanoplates through an etching process, respectively, enabling visual analysis of ARGs with distinguishing color changes. Meanwhile, numerous Cu 2+ and Hg 2+ triggered the amplified PEC variations via reacting with the photoactive layers of CuS/CdS and ZnS, respectively. Thus, a rapid and ultrasensitive colorimetric/PEC dual-mode detection of multiple ARGs was achieved with the detection limit down to 17.2 aM. Furthermore, such dual-mode bioassay could discriminate single-base mismatch and successfully determine ARGs in E. coli plasmids and sludge samples, holding great promise for point-of-care genetic diagnostics.

Ferromagnetic (FM) states with high Curie temperatures ( T c ) and strong spin-orbit coupling (SOC) are indispensable for the long-sought room-temperature quantum anomalous Hall (QAH) effects. Here, we propose a two-dimensional (2D) iron-based monolayer MgFeP that exhibits a notably high FM T c (about 1525 K) along with exceptional structural stabilities. The unique multiorbital nature in MgFeP, where localized d x 2 - y 2 and d xz / yz orbitals coexist with itinerant d xy and d z 2 orbitals, renders the monolayer a Hund's metal and in an orbital-selective Mott phase (OSMP). This OSMP triggers an FM double exchange mechanism, rationalizing the high T c in the Hund's metal. This material transitions to a QAH insulator upon consideration of the SOC effect. By leveraging orbital selectivity, the QAH band gap can be enlarged by more than two times (to 137 meV). Our findings showcase Hund's metals as a promising material platform for realizing high-performance quantum topological electronic devices.

Amorphous nanomaterials have drawn extensive attention owing to their unique features, while amorphization on noble metal nanomaterials still remains formidably challenging. Herein, we demonstrate a universal strategy to synthesize amorphous Pd-based nanomaterials from unary to quinary metals through the introduction of phosphorus (P). The amorphous Pd-based nanoparticles (NPs) exhibit generally promoted oxygen reduction reaction (ORR) activity and durability compared with their crystalline counterparts. Significantly, the quinary P-PdCuNiInSn NPs, benefiting from the amorphous structure and multimetallic component effect, exhibit mass activities as high as 1.04 A mg Pd -1 and negligible activity decays of 1.8% among the stability tests, which are much better than values for original Pd NPs (0.134 A mg Pd -1 and 28.4%). Experimental and theoretical analyses collectively reveal that the synergy of P-induced amorphization and the expansion of metallic components can considerably lower the free energy changes in the rate-determined step, thereby explaining the positive correlation with the catalytic activity.

Multifunctional intelligent wearable electronics, providing integrated physiological signal analysis, storage, and display for real-time and on-site health status diagnosis, have great potential to revolutionize health monitoring technologies. Advanced wearable systems combine isolated digital processor, memory, and display modules for function integration; however, they suffer from compatibility and reliability issues. Here, we introduce a flexible multifunctional electrolyte-gated transistor (EGT) that integrates synaptic learning, memory, and autonomous discoloration functionalities for intelligent wearable application. This device exhibits synergistic light absorption coefficient changes during voltage-gated ion doping that modulate the electrical conductance changes for synaptic function implementation. By adaptively changing color, the EGT can differentiate voltage pulse inputs with different frequency, amplitude, and duration parameters, exhibiting excellent reversibility and reliability. We developed a smart wearable monitoring system that incorporates EGT devices and sensors for respiratory and electrocardiogram signal analysis, providing health warnings through real-time and on-site discoloration. This study represents a significant step toward smart wearable technologies for health management, offering health evaluation through intelligent displays.

Local electric field induced by the lightning-rod effect attracts great attention for regulating the local microenvironment and electronic properties of active sites. Nevertheless, local electric-field-assisted applications are mainly limited to metals with strong surface plasmonic resonance properties (e.g., Au, Ag, and Cu). Herein, we fabricate RuCu snow-like nanosheets (SNSs) with high-curvature nanotips for enhancing the hydrogen oxidation reaction (HOR) and hydrogen evolution reaction (HER). Theoretical simulations show that RuCu SNSs can induce a strong local electric field around the sharp nanotips, which favors the accumulation of OH - for HOR and H + for HER. Cu incorporation can modulate the binding strength of OH* and H*, leading to significantly enhanced HOR and HER performance. Impressively, the mass activity of RuCu SNSs for alkaline HOR is 31.3 times higher than that of RuCu nanocrystals without sharp tips. Besides, the required overpotential for reaching 10 mA cm -2 during HER over RuCu SNSs is 14.0 mV.

Bioorthogonal prodrug therapies offer an intriguing two-component system that features enhanced circulating stability and controlled activation on demand. Current strategies often deliver either the prodrug or its complementary activator to the tumor with a monomechanism targeted mechanism, which cannot achieve the desired antitumor efficacy and safety profile. The orchestration of two distinct and orthogonal mechanisms should overcome the hierarchical heterogeneity of solid tumors to improve the delivery efficiency of both components simultaneously for bio-orthogonal prodrug therapies. We herein developed a dual-mechanism targeted bioorthogonal prodrug therapy by integrating two orthogonal, receptor-independent tumor-targeting strategies. We first employed the endogenous albumin transport system to generate the in situ albumin-bound, bioorthogonal-caged doxorubicin prodrug with extended plasma circulation and selective accumulation at the tumor site. We then employed enzyme-instructed self-assembly (EISA) to specifically enrich the bioorthogonal activators within tumor cells. As each targeted delivery mode induced an intrinsic pharmacokinetic profile, further optimization of the administration sequence according to their pharmacokinetics allowed the spatiotemporally controlled prodrug activation on-target and on-demand. Taken together, by orchestrating two discrete and receptor-independent targeting strategies, we developed an all-small-molecule based bioorthogonal prodrug system for dual-mechanism targeted anticancer therapies to maximize therapeutic efficacy and minimize adverse drug reactions for chemotherapeutic agents.

Facet-dependent toxic metal adsorption of iron oxides widely occurred in natural environments. It is known that organic acids can alter the adsorption behaviors of trace elements by cooperative or competitive effects. However, the coadsorption mechanisms of the specific facets are still not fully understood. In the current investigation, Cr(VI) adsorption onto the lepidocrocite (γ-FeO(OH))-exposed facets in the presence of oxalic acid (OA) was studied using macroexperiments, in situ attenuated total reflectance Fourier transform infrared spectroscopy, X-ray adsorption fine structure, and density functional theory calculations. Rod-like lepidocrocite (R-LEP) with a high ratio of {001}/{010} facet showed excellent Cr(VI) adsorption capacity than that of plate-like lepidocrocite (P-LEP, the dominant facet is {010}) in the absence/presence of OA. Interestingly, OA reacted with R-LEP would be easier to diminish Cr(VI) adsorption than with P-LEP. The competitive adsorption occurred on the {001} facet due to the formation of inner-sphere OA configurations (monodentate mononuclear and bidentate mononuclear structures) and a bidentate binuclear Cr(VI) complex. However, OA coordinated with {010} facets via the outer-sphere complexes, while Cr(VI) could form a protonated monodentate binuclear configuration. These observations suggest that the competitive adsorption processes between OA and Cr(VI) exhibit facet dependence. Furthermore, lepidocrocite-exposed facets determine the interfacial interactions and geochemical behaviors of Cr(VI) in polluted environments.

Nitromethane (NM) is the simplest nitroalkane fuel and has demonstrated potential usage as propellant and fuel additive. Thus, understanding the combustion characteristics and chemistry of NM is critical to the development of hierarchical detailed kinetic models of nitro-containing energetic materials. Herein, to further investigate the ignition kinetics of NM and supplement the experimental database for kinetic mechanism development, an experimental and kinetic modeling analysis of the ignition delay times (IDTs) of NM behind reflected shock waves at high fuel concentrations is reported against previous studies. Specifically, the IDTs of NM are measured via a high-pressure shock tube within the temperature from 900 to 1150 K at pressures of 5 and 10 bar and equivalence ratios of 0.5, 1.0, and 2.0. Brute-force sensitivity analysis and chemical explosive mode analysis in combination with reaction path analysis are employed to reveal the fundamental ignition kinetics of NM. Finally, a skeletal mechanism for NM is derived via the combination of directed relation graph-based methods, which demonstrates good prediction accuracy of NM ignition and flame speeds. The present work should be valuable for understanding the combustion chemistry of NM and the development of the fundamental reaction mechanism of nitroalkane fuels., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Given the lack of timely evaluation of the well-received selenium fortification, a neat lateral-flow chromatographic solution was constructed here by using the recently identified urinary selenosugar (Sel) as a strongly indicative marker. As there are no ready-made receptors for this synthetic standard, phenylboronic acid (PBA) esterification and Dolichos biflorus agglutinin (DBA) affinity joined up to pinch and pin down the analyte into a sandwich-type glycol complex. Pilot lectin screening on homemade glycan microarrays verified such a new pairing between dual recognizers as PBA-Sel-DBA with a firm monosaccharide-binding constant. To quell the sample autofluorescence, europium nanoparticles with efficient long-life afterglow were employed as conjugating probes under 1 μs excitation. After systematic process optimizations, the prepared Sel-dipstick achieved swift and sensitive fluorometry over the physiological level of the target from 0.1 to 10 μM with a detection limit down to 0.06 μM. Further efforts were made to eliminate matrix effects from both temperature and pH via an approximate formula. Upon completion, the test strips managed to quantify the presence of Sel in not just imitated but real human urine, with comparable results to those in the references. As far as we know, this would be the first in-house prototype for user-friendly and facile diagnosis of Se nutrition with fair accuracy as well as selectivity. Future endeavors will be invested to model a more traceable Se-supplementary plan based on the rhythmic feedback of Sel excretion.

A mesoporous cobalt-based metal-organic framework (LCU-606) was synthesized based on a hexagonal bipyramid Co 8 (μ 4 -O) 3 cluster and an N , N , N ', N '-tetrakis-(4-benzoic acid)-1,4-phenylenediamine ligand (H 4 TBAP). LCU-606 featuring large pore diameters of 21.7 Å and exposed Lewis-acid metal sites could serve as an excellent heterogeneous catalyst for CO 2 cycloaddition reaction with various epoxide substrates under mild conditions (1 atm CO 2 , 60 °C, and solvent free). In particular, when extending the substrates to bulkier ones, LCU-606 still shows high catalytic efficiency on account of the large pore aperture. Also, LCU-606 demonstrates high recyclability and stability in consecutive catalytic runs. Therefore, the high efficiency, recyclability, and generality on CO 2 catalytic cycloaddition make LCU-606 a very promising heterogeneous catalyst for CO 2 chemical fixation.

We report on the Tomonaga-Luttinger liquid (TLL) behavior in fully degenerate 1D Dirac Fermions. A ternary van der Waals material Nb 9 Si 4 Te 18 incorporates in-plane NbTe 2 chains, which produce a 1D Dirac band crossing Fermi energy. Tunneling conductance of electrons confined within NbTe 2 chains is found to be substantially suppressed at Fermi energy, which follows a power law with a universal temperature scaling, hallmarking a TLL state. The obtained Luttinger parameter of ∼0.15 indicates a strong electron-electron interaction. The TLL behavior is found to be robust against atomic-scale defects, which might be related to the Dirac electron nature. These findings, combined with the tunability of the compound and the merit of a van der Waals material, offer a robust, tunable, and integrable platform to exploit non-Fermi liquid physics.

Immunotherapy is an advanced therapeutic strategy of cancer treatment but suffers from the issues of off-target adverse effects, lack of real-time monitoring techniques, and unsustainable response. Herein, an ultrasmall Au nanocluster (NC)-based theranostic probe is designed for second near-infrared window (NIR-II) photoluminescence (PL) imaging-guided phototherapies and photoactivatable cancer immunotherapy. The probe (Au 44 MBA 26 -NLG for short) is composed of atomically precise and NIR-II emitting Au 44 MBA 26 NCs (here MBA denotes water-soluble 4-mercaptobenzoic acid) conjugated with immune checkpoint inhibitor 1-cyclohexyl-2-(5H-imidazo[5,1- a ]isoindol-5-yl)ethanol (NLG919) via a singlet oxygen ( 1 O 2 )-cleavable linker. Upon NIR photoirradiation, the Au 44 MBA 26 -NLG not only enables NIR-II PL imaging of tumors in deep tissues for guiding tumor therapy but also allows the leverage of photothermal property for cancer photothermal therapy (PTT) and the photogenerated 1 O 2 for photodynamic therapy (PDT) and releasing NLG919 for cancer immunotherapy. Such a multiple effect modulated by Au 44 MBA 26 -NLG prompts the proliferation and activation of effector T cells, upshifts systemic antitumor T-lymphocyte (T cell) immunity, and finally suppresses the growth of both primary and distant tumors in living mice. Overall, this study may provide a promising theranostic nanoplatform toward NIR-II PL imaging-guided phototherapies and photoactivatable cancer immunotherapy.

Multicomponent metallic nanomaterials with unconventional phases show great prospects in electrochemical energy storage and conversion, owing to unique crystal structures and abundant structural effects. In this review, we emphasize the progress in the strain and surface engineering of these novel nanomaterials. We start with a brief introduction of the structural configurations of these materials, based on the interaction types between the components. Next, the fundamentals of strain, strain effect in relevant metallic nanomaterials with unconventional phases, and their formation mechanisms are discussed. Then the progress in surface engineering of these multicomponent metallic nanomaterials is demonstrated from the aspects of morphology control, crystallinity control, surface modification, and surface reconstruction. Moreover, the applications of the strain- and surface-engineered unconventional nanomaterials mainly in electrocatalysis are also introduced, where in addition to the catalytic performance, the structure-performance correlations are highlighted. Finally, the challenges and opportunities in this promising field are prospected.

The rational design of an oxygen electrocatalyst with low cost and high activity is greatly desired for realization of the practical water-splitting industry. Herein, we put forward a rational method to construct nonprecious-metal catalysts with high activity by designing the microstructure and modulating the electronic state. Iron (Fe)-doped Ni 2 P hollow polyhedrons decorated with nitrogen-doped carbon (Fe-Ni 2 P/NC HPs) are prepared by a sequential metal-organic-framework-templated strategy. Benefiting from the strong electronic coupling, rapid charge-transfer capability, and abundant catalytic active sites, the obtained Fe-Ni 2 P/NC HPs exhibit an impressive electrocatalytic performance toward the oxygen evolution reaction (OER) with an ultralow overpotential of 228 mV at a current density of 10 mA cm -2 and a small Tafel slope of 33.4 mV dec -1 , superior to the commercial RuO 2 and most reported electrocatalysts. Notably, this catalyst also shows long durability with an almost negligible activity decay over 210 h for the OER. Combining density functional theory calculations with experiments demonstrates that the doped Fe and the incorporated carbon effectively modulate the electronic structure, enhance the conductivity, and greatly reduce the energy barrier of the rate-determining step in the process of OER. Thus, fast OER kinetics is realized. Moreover, this synthetic strategy can be extended to the synthesis of Fe-NiS 2 /NC HPs and Fe-NiSe 2 /NC HPs with excellent OER performance and long-term durability. This work furnishes an instructive idea in pursuit of nonprecious-metal materials with robust electrocatalytic activity and long durability.

Inflammatory infiltration and bone destruction are important pathological features of rheumatoid arthritis (RA), which originate from the disturbed niche of macrophages. Here, we identified a niche-disrupting process in RA: due to overactivation of complement, the barrier function of VSIg4 + lining macrophages is disrupted and mediates inflammatory infiltration within the joint, thereby activating excessive osteoclastogenesis and bone resorption. However, complement antagonists have poor biological applications due to superphysiologic dose requirements and inadequate effects on bone resorption. Therefore, we developed a dual-targeted therapeutic nanoplatform based on the MOF framework to achieve bone-targeted delivery of the complement inhibitor CRIg-CD59 and pH-responsive sustained release. The surface-mineralized zoledronic acid (ZA) of ZIF8@CRIg-CD59@HA@ZA targets the skeletal acidic microenvironment in RA, and the sustained release of CRIg-CD59 can recognize and prevent the complement membrane attack complex (MAC) from forming on the surface of healthy cells. Importantly, ZA can inhibit osteoclast-mediated bone resorption, and CRIg-CD59 can promote the repair of the VSIg4 + lining macrophage barrier to achieve sequential niche remodeling. This combination therapy is expected to treat RA by reversing the core pathological process, circumventing the pitfalls of traditional therapy.

Oral delivery of probiotics has been a promising method for treatment of inflammatory bowel diseases (IBDs). However, probiotics always suffer from substantial loss of viability due to the harsh gastrointestinal conditions, especially the highly acidic environment in the stomach and bile salts in the intestine. In addition, to overcome the challenging conditions, an ideal delivery of probiotics requires the on-demand release of probiotics upon environmental response. Herein, a novel nitroreductase (NTR) labile peptidic hydrogel based on supramolecular self-assembly is demonstrated. The efficient encapsulation of typical probiotic Escherichia coli Nissle 1917 (EcN) into supramolecular assemblies yielded a probiotic-loaded hydrogel (EcN@Gel). Such a hydrogel adequately protected EcN to improve its viability against harsh acid and bile salt environments during oral delivery. The upregulated NTR in the intestinal tract triggered the disassembly of the hydrogel and accomplished the controlled release of EcN locally. In ulcerative colitis (UC)-bearing mice, EcN@Gel showed significantly enhanced therapeutic efficacy by downregulating proinflammatory cytokines and repairing the intestinal barrier. Moreover, EcN@Gel remolded the gut microbiome by increasing the diversity and abundance of indigenous probiotics, contributing to ameliorated therapies of IBDs. The NTR-labile hydrogel provided a promising platform for the on-demand delivery of probiotics into the intestinal tract.

Gold nanoparticle (AuNP) decoration is a commonly used method to enhance the optical responses in many applications such as photocatalysis, biosensing, solar cells, etc. The morphology and structure of AuNPs are essential factors determining the functionality of the sample. However, tailoring the growth mechanism of AuNPs on an identical surface is not straightforward. In this study, AuNPs were deposited on the surface of a perovskite thin film, strontium niobate (SNO), using pulsed laser deposition (PLD). AuNPs exhibited a dramatic variation in their growth mechanisms, depending on whether they were deposited on SNO thin films grown on magnesium oxide (SNO/MgO) or strontium titanate (SNO/STO) substrates. On SNO/MgO, the Au aggregates form large NPs with an average size of up to 3500 nm 2 . These AuNPs are triangular with sharp edges and corners. The out-of-plane direction of growth is favored, and the surface coverage ratio by AuNPs is low. When deposited on SNO/STO, the average size of AuNPs is much smaller, i.e., ∼250 nm 2 . This reduction in the average size is accompanied by an increase in the number density of NPs. AuNPs on SNO/STO have a round shape and high coverage ratio. Such an impact from the substrate selection on the AuNP structure is significant when the sandwiched SNO film is below 80 nm thickness and is weakened for 200 nm of SNO films. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to characterize all samples. Strain analysis was used to explain the growth mechanism of AuNPs. The average height of AuNPs was measured by using atomic force microscopy (AFM). Ellipsometry in the visible-near-infrared (vis-NIR) region was used to characterize the optical response of all samples. AuNP-decorated SNO/MgO and SNO/STO thin films exhibit different optical properties, with only gold-decorated SNO/MgO samples showing a size-dependent epsilon-near-zero behavior of nanoparticles. These results provide an additional route to control the structure of AuNPs. They can be used for various plasmonic applications like the design and development of strain-engineered gold-nanoparticle-decorated devices for surface-enhanced Raman spectroscopy (SERS) and photocatalysis., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)