High active organometallic catalyst always faced neck in biological sensing due to poor biocompatibility and scarce catalytic triggered signal release reactions, although it has already demonstrated extremely high application potential in biological orthogonal catalytic fields. Here, we firstly showed a novel organoiridium catalyst Ir1@CD by assembling beta-cyclodextrin (beta-CD) and adamantane functionalized pyridine-amide iridium complexes Ir1, which was characterized by Two-dimensional rotating-frame overhauser spectroscopy (2D ROSEY) 1H NMR and Isothermal Titration Calorimetry ITC (bonding constant Ks similar to 10(5) M- 1). Over 20.0 % yield increase was obtained when Ir1@CD was used as catalysts compared to Ir1 for trimethyl p-benzoquinone TMBQ hydrogenation, which demonstrated that beta-CD could significantly enhanced catalytic activity of Ir1. Further, a robust biomimetic catalytic hydrogen transfer sensing system was established by combining Ir1@CD with new stable quinone-hydrogenation-cleavage probes PMNQ. The sensing system presented higher fluorescence enhancement factor (19.7-fold), good linear responses ranged from 1.56 to 50 mu M, lower limits of detection LOD (160.0 nM) for cofactor NADH, and could be successfully applied in intracellular imaging of NADH. The provided biocatalytic strategy will also be expected to use in other fields, such as biomimetic organometallic catalysts, drug delivery and many more chemical-biological technologies.

The widespread use of organophosphate pesticides (OPs) critically endangers food safety and environmental health, necessitating highly sensitive detection strategies. Herein, we report a d-band modulated Au@RuPt core-shell nanozyme for ultrasensitive OP detection via an oxygen reduction reaction (ORR) inhibition mechanism. The Au@RuPt nanodots (RuPt shell ∼1.02 nm on Au core ∼3.08 nm) exhibit enhanced ORR activity (Tafel slope: 49.89 mV dec-1) with a dominant four-electron pathway. Mechanistic studies reveal that Ru incorporation upshifts the d-band center, promoting thiocholine (TCh) chemisorption and consequent ORR poisoning. The biosensing mechanism relies on TCh-induced ORR inhibition and its recovery upon OP-mediated acetylcholinesterase inactivation, enabling a "signal-on" readout. The sensor exhibits a detection limit of 0.0264 ng mL-1 toward phoxim, alongside excellent specificity, reproducibility (RSD < 1.62%), stability (>94.6% after 30 days), and real-sample recoveries (96.3-104.6%). It also enables in situ pesticide monitoring on plant leaves and AChE activity evaluation with IC50 quantification for multiple OPs. This work establishes an alloy nanozyme platform for ORR-based electrochemical biosensing, opening new avenues for point-of-need applications in agricultural safety, toxicology, and clinical diagnostics.

Amanitin (AMA), a highly toxic octapeptide from Amanita mushrooms, poses severe poisoning risks due to misidentification. Herein, we developed a flexible SERS substrate integrating MIL-101(Cr), gold nanobipyramids (AuBPs) and cellulose nanofibers (CNF) with a "dual-sieve" impurity-exclusion mechanism. This platform achieves ultra-sensitive (LOD: 10-8 mg/mL) and rapid discrimination of α-, β-, and γ-AMA subtypes, with robust anti-matrix interference performance. It enables efficient AMA subtyping, providing a portable, reliable strategy for emergency mushroom poisoning screening and food safety diagnostics.

Magic-sized semiconductor clusters (MSCs) synthesized in organic solvents typically exhibit poor compatibility with aqueous media, which hampers electron transfer and leads to weak electrochemiluminescence (ECL), thereby limiting their biological and environmental applications. Here we report that cation-induced assembly confers aqueous stability on Cd15Se12 MSCs and simultaneously boosts their ECL efficiency. Using cysteine (Cys) as a stabilizing ligand, we prepared water-dispersible Cd15Se12-Cys MSCs and introduced multivalent metal cations (Mn+=Zn2+, Cd2+, K+, Na+, Al3+) to electrostatically bind the surface carboxylate groups, thereby driving spontaneous intercluster assembly. The assembled Cd15Se12-Cys-Mn+ MSCs exhibited a 10-fold enhancement in ECL intensity compared to unassembled counterparts, along with excellent signal stability over 1000 s of continuous operation. Mechanistic studies revealed that the cation valence critically dictates the assembly mode and ECL efficiency. Notably, Zn2+-modified assemblies functioned as highly efficient ECL emitters in a biosensing platform, enabling sensitive lactate detection in sweat with a broad linear range (0.01-50 mM). This work establishes cation-induced assembly as a general strategy to achieve aqueous-stable MSCs with enhanced ECL performance, opening new opportunities for their application in biosensing and environmental monitoring.

Abstract Zearalenone (ZEN) contamination in grains poses a serious threat to human and animal health, yet existing imaging-based platforms for rapid visualized detection remain limited by insufficient sensitivity, limited luminescence efficiency, and poor signal stability, hindering further practical applications. Herein, a portable smartphone-assisted electrochemiluminescence (ECL) imaging platform was developed for ultrasensitive and visualized detection of ZEN based on protamine-enhanced 6-aza-2-thiothymine-stabilized gold nanoclusters (Prot/ATT-Au NCs) synthesized by a protein-assisted assembly strategy. The resulting Prot/ATT-Au NCs achieved a 108-fold enhancement in ECL intensity relative to bare ATT-Au NCs and demonstrated an ECL efficiency approximately 5.01-fold higher than that of the benchmark Ru(bpy)32+ system, enabling naked-eye-visible green ECL emission. This enhancement was attributed to Prot-induced hydrogen-bonding and electrostatic confinement that suppressed nonradiative decay and facilitated radiative transitions. Integrated with catalytic hairpin assembly amplification, the developed ECL imaging system allowed ZEN to be visually quantified over a wide linear range of 1 pg/mL to 10 μg/mL with a detection limit of 0.38 pg/mL, along with excellent specificity, stability, reproducibility, and real-sample recoveries. Furthermore, it was applied for the determination of ZEN in naturally contaminated corn samples. This work provides a facile strategy for engineering high-performance ECL emitters and offers a robust route toward portable food safety monitoring.

The widespread use of organophosphate pesticides (OPs) critically endangers food safety and environmental health, necessitating highly sensitive detection strategies. Herein, we report a d-band modulated Au@RuPt core-shell nanozyme for ultrasensitive OP detection via an oxygen reduction reaction (ORR) inhibition mechanism. The Au@RuPt nanodots (RuPt shell similar to 1.02 nm on Au core similar to 3.08 nm) exhibit enhanced ORR activity (Tafel slope: 49.89 mV dec(-1)) with a dominant four-electron pathway. Mechanistic studies reveal that Ru incorporation upshifts the d-band center, promoting thiocholine (TCh) chemisorption and consequent ORR poisoning. The biosensing mechanism relies on TCh-induced ORR inhibition and its recovery upon OP-mediated acetylcholinesterase inactivation, enabling a "signal-on" readout. The sensor exhibits a detection limit of 0.0264 ng mL(-1) toward phoxim, alongside excellent specificity, reproducibility (RSD < 1.62%), stability (>94.6% after 30 days), and real-sample recoveries (96.3-104.6%). It also enables in situ pesticide monitoring on plant leaves and AChE activity evaluation with IC50 quantification for multiple OPs. This work establishes an alloy nanozyme platform for ORR-based electrochemical biosensing, opening new avenues for point-of-need applications in agricultural safety, toxicology, and clinical diagnostics.

The development of simple, cost-effective, and reliable sensing strategies for perfluorooctanoic acid (PFOA) is imperative for environmental safety. In this work, a novel label-and probe-free electrochemical sensor is constructed by integrating a highly redox-active ternary FeCoNi Prussian blue analogues (PBAs) core with a molecularly imprinted polypyrrole (mPPy) shell. The ternary FeCoNi PBAs core acts as a robust internal signal reporter, exhibiting more intense and well-defined intrinsic redox activity compared to its binary (FeCo-, FeNi-PBAs) counterparts, owing to synergistic mixed-valence interactions and richer redox chemistry. The conformal mPPy shell plays a triple role: (1) enhancing the overall conductivity, (2) protecting the PBAs core against dissolution, and (3) enabling the specific capture of PFOA. The binding of insulating and hydrophobic PFOA molecules within the imprinted cavities impedes electron/ion transfer to the PBAs core, causing a measurable decrease in its oxidation peak current. This allows for the quantitative determination of PFOA without requiring any external labels or probes. The sensor achieves a wide linear range (1.0 pM-5.0 nM), a low detection limit (0.031 pM), excellent selectivity, satisfactory reproducibility (RSD < 1.57%) and long-term stability (drift<1.28% after 30 days), good reusability (similar to 96.8% signal retention after five regeneration cycles), and reliable performance in actual environmental water matrices. The study not only delivers a high-performance PFOA sensor but also highlights the advantage of ternary PBAs for building sensitive, direct signaltransduction platforms targeting non-electroactive pollutants.

Objectives: The identification of early warning biomarkers and associated molecular mechanisms of sudden cardiac death (SCD) caused by acute coronary syndrome (ACS) through the analysis of peripheral blood plasma extracellular vesicles (EVs) remains a significant gap in current knowledge. We aimed to screen for novel EV metabolic markers and validate their prediction ability, thereby providing novel early diagnostic biomarkers for the risk of sudden death due to ACS; based on the premise that EVs mirror cellular metabolic stress, we hypothesized that specific EV metabolic signatures can predict SCD risk in ACS patients. Methods: In this nested case–control study, plasma EVs from 18 non-ST-segment elevation ACS (NSTE-ACS), 21 ST-segment elevation myocardial infarction, 16 ACS-related SCD patients, and 41 matched controls were isolated and characterized in accordance with the Minimal Information for Studies of Extracellular Vesicles 2018 guidelines. We performed a combined liquid chromatography-tandem mass spectrometry–based metabolomic and proteomic analysis of plasma EVs, conducted multiomics integration for pathway and network analysis, and validated candidate biomarkers by enzyme-linked immunosorbent assay. Receiver operating characteristic curve analysis and multivariate/univariate statistical methods were applied to evaluate the SCD risk predictive value of the identified markers. Results: We identified 27 differential metabolites associated with the progression of SCD in plasma EVs of ACS patients. The combined analysis suggested that glycolysis and the tricarboxylic acid cycle might be key metabolic pathways in SCD. Notably, EV-derived pyruvate and lactic dehydrogenase B (LDHB) levels were significantly elevated in SCD patients compared with controls ( P < 0.05), despite no differences in plasma concentrations, suggesting EV-derived pyruvate and LDHB as early biomarkers to predict SCD in ACS patients. Integration of EV-derived pyruvate and LDHB with traditional biomarkers (creatine kinase isoenzyme and myoglobin) improved SCD risk prediction (area under the curve: 0.786 for pyruvate + LDHB; area under the curve: 0.9 when combined with creatine kinase isoenzyme), underscoring their potential for enhancing risk stratification. Conclusion: In this nested case–control study of ACS patients, multiomics profiling of plasma EVs revealed altered distinct metabolic signatures in SCD cases, particularly the LDHB–pyruvate–spermine–spermidine network involved in glycolysis and the tricarboxylic acid cycle. LDHB and pyruvate emerged as codiagnostic biomarkers, enhancing predictive accuracy for cardiovascular events when combined with clinical indicators.

Structural instability and sluggish lithium-ion (Li+) kinetics of spinel NiCo2O4 anodes severely hinder their applications in high-energy-density lithium-ion batteries. Mesocrystalline structures exhibit promising potential in balancing structural stability and enhancing reaction kinetics. However, their controlled synthesis mechanisms remain elusive. Herein, a substrate interface engineering strategy is developed to achieve controllable synthesis of mesocrystalline and polycrystalline NiCo2O4 nanorods. Remarkably, mesocrystalline NiCo2O4 exhibits a high capacity retention rate of 85.7% after 500 cycles at 2 A/g, attributed to its porous structure facilitating Li+ transport kinetics and unique stress-buffering effect validated by ex-situ TEM. Theoretical calculations and interfacial chemical analysis reveal that substrate-crystal surface engineering regulates the nucleation-growth pathways: Acid-treated nickel foam enables epitaxial growth via lattice matching, acting as a low-interfacial-energy template to reduce nucleation barriers and promote low-temperature oriented crystallization. In contrast, carbon cloth requires high-temperature thermal activation to overcome surface diffusion barriers induced by elevated interfacial energy. This substrate-driven crystallization kinetic modulation overcomes the limitations of random nucleation in conventional hydrothermal synthesis. The established substrate-crystal interfacial interaction model not only clarifies the kinetic essence of crystal orientation regulation but also provides a universal theoretical framework for lattice-matching design and mesostructural optimization of advanced electrode materials.

The development of photosynthetic biological systems (PBSs) presents a promising approach to mitigating global climate change. However, the practical application of PBSs remains hindered by their low product yields. Key determinants of production efficiency include light utilization, electron transfer efficiency, and catalyst stability. To address these challenges, we developed a high-performance Cupriavidus necator/CdS@Au@Poly dimethyl diallyl ammonium chloride ( C. necator/CdS@Au@PDDA) biohybrid system for the photocatalytic conversion of CO2 into bioplastic poly(3-hydroxybutyrate) (PHB). The incorporation of Au nanoclusters extends the visible light absorption range and alleviates photocorrosion of CdS, while the PDDA modification enhances electron transfer rates and enables the material to firmly adhere to the bacterial surface. In situ H2 production by CdS@Au@PDDA drives CO2 fixation through bacterial metabolic pathways, achieving a quantum efficiency of 2.76 % +/- 0.22 % and a maximum PHB yield of 53.6 +/- 5.2 mg/L, representing the highest yield reported for C. necator-based artificial PBSs. This biohybrid system demonstrates the effective integration of advanced nanomaterials with microbial processes, offering a robust platform for sustainable bioplastic production through carbon-neutral artificial photosynthesis technology and providing a novel perspective for addressing the global challenge of microplastic pollution. (c) 2026 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.

An S-scheme Bi 2 WO 6 /BiOBr photoelectrochemical biosensor coupled with CHA–CRISPR/Cas12a cascade amplification enables ultrasensitive piR-823 detection for colorectal cancer.

A disposable glove-derived flexible biosensor employs vertex-selective Pd-Pt nanodendrites catalyzing dissolved oxygen-mediated electrochemiluminescence, quenched by organophosphorus poisoning for on-site detection.

Exosomal piR-823 is a promising specific biomarker for colorectal cancer, yet its ultrasensitive detection remains challenging due to its extremely low abundance and high sequence complexity. Herein, we developed a cascaded CHA-CRISPR/Cas12a photoelectrochemical (PEC) sensing platform enabled by an S-scheme Bi2WO6/BiOBr heterojunction for the reliable detection of piR-823. The flower-like spherical Bi2WO6/BiOBr heterojunction exhibits enhanced visible-light absorption and efficient charge transfer arising from the S-scheme structure, which establishes a strong photoactive basis for the PEC platform. By integrating catalytic hairpin assembly with CRISPR/Cas12a trans-cleavage activity, a cascaded signal amplification strategy is established, which significantly improves the detection sensitivity. Under optimized conditions, the platform shows a distinct negative correlation between transient photocurrent and the logarithm of piR-823 concentration (1.0-1.0 × 106 fM), with an ultralow detection limit of 0.34 fM (S/N = 3). It also demonstrates high specificity, good reproducibility, and satisfactory recovery (96.87%-103.41%) in exosome lysate. This work not only presents an efficient PEC biosensing platform for piRNA analysis but also offers guidance for the rational construction of S-scheme heterojunctions in high-performance PEC biosensors, holding great promise for early colorectal cancer diagnosis and prognostic monitoring.

A green, ultralow-dose, self-catalytic electrochemiluminescence probe based on Cu single-atom carbon dots enables label-free imaging of cell-matrix adhesion, requiring neither exogenous coreactants nor excess luminophore usage.

Cancer is now a leading cause of human death worldwide and discovering an underlying cancer risk is essential to enhance the survival rates of the patients. Herein, we report a facile and sensitive electrochemical biosensing method for the determination of matrix metalloproteinase-2 (MMP-2), a potential indicator in most solid tumors. The core of the method is the use of a well-designed peptide probe with tunable membrane penetration activity. Specifically, the membrane penetration activity of the peptide probe is initially inhibited by a blocking domain through electrostatic interaction. Once the probe is selectively recognized and cleaved by MMP-2, its membrane penetration activity is switched on, leading to large amounts of methylene blue molecules being released from liposomes. As a result, remarkably amplified electrochemical responses are obtained for the determination of target MMP-2. Under optimized conditions, our method has displayed a good sensing performance, showing a wider linear range from 50 fg/mL to 10ng/mL and a low limit of detection at 13.3 fg/mL. Moreover, the method has been successfully applied to MMP-2 determination in the mimic tumor microenvironment and serum samples and proved the feasibility of the selective identification of cancer patients. Therefore, our method may suggest a potential use in the determination of protease-specific tumor biomarkers for pan-cancer screening.

ObjectiveTo obtain differential spectral characteristics of etomidate and its structural analogues, and to establish a rapid identification method using surface-enhanced Raman spectroscopy （SERS） combined with machine learning algorithms for distinguishing etomidate and its analogues.MethodsSilver nanoparticles （AgNPs） were used as the SERS substrate to collect SERS spectra of etomidate, metomidate, propoxate, and isopropoxate at two concentrations of 1×10-4 and 1×10-5 mol/L. SERS spectra were also obtained from blood and urine samples containing 1×10-5 mol/L of etomidate, metomidate, propoxate, and isopropoxate, as well as from confiscated e-cigarette oil containing etomidate. Uniform manifold approximation and projection （UMAP） was employed for nonlinear dimensiona-lity reduction and visualization, and a classification model based on the XGBoost algorithm was constructed to enable discriminant analysis of these four structurally highly similar compounds.ResultsMinor characteristic peak shifts （5-3 cm-1） were identified in the range of 1 398-811 cm-1. Qualitative identification of the compounds in serum, urine and e-cigarette oil samples was achieved without pretreatment. After UMAP dimensionality reduction, distinct clustering separation among different substances was observed. The XGBoost model achieved 100% classification accuracy on the test set. Feature weight analysis revealed that C-N stretching vibration （841 cm-1）, C=O stretching vibration （1 367 cm-1）, and C-O-C asymmetric vibration （1 049 cm-1） were the key spectral bands for discrimination.ConclusionThe combination of SERS and machine learning can effectively amplify subtle differences in molecular structures, enabling rapid and accurate identification of etomidate and its analogues. This approach is suitable for on-site rapid screening in forensic toxicology.

Simultaneous detection of metabolites and proteins─two chemically and functionally distinct classes of biomolecules─in complex biofluids remains a significant analytical hurdle, yet is critical for early and accurate disease diagnosis. These difficulties arise from intrinsic disparities in molecular abundance, physicochemical properties, and detection mechanisms. Such analytical limitations span a wide range of disease contexts and are exemplified by acute coronary syndrome-induced sudden cardiac death (ACS-SCD), where intertwined metabolic and proteomic dysregulation obscures early diagnostic cues and necessitates robust, multiplexed detection strategies. Here, we present a dual-signal surface-enhanced Raman scattering (SERS) platform─termed Gemini─for ultrasensitive, cross-category quantification of pyruvate (a metabolite) and lactate dehydrogenase B (LDHB, a protein) in plasma-derived exosomes. The system integrates antibody-functionalized gold nanoparticles for LDHB recognition with a boronate-based SERS nanotag responsive to hydrogen peroxide (H2O2) generated from a pyruvate oxidase (POx)-mediated cascade. This strategy yields two spectrally distinct Raman signals within a single assay, enabling ratiometric and interference-free detection. Gemini achieves detection limits of 2.415 μM for pyruvate and 0.032 ng/mL for LDHB. When combined with a support vector machine (SVM) classifier, the platform accurately distinguishes ACS-SCD patients from healthy controls with 85% accuracy (90% sensitivity, 80% specificity), showing diagnostic performance comparable to conventional methods (AUC = 0.82 vs 0.79). This study demonstrates a multiplexed SERS framework for integrated metabolic-proteomic diagnostics and provides a clinically scalable strategy for early cardiovascular risk assessment. Moreover, the Gemini platform offers a broadly applicable paradigm for precision diagnostics across diverse pathophysiological conditions.

Electrochemical technology provides unique opportunities to create an environment‐friendly and sustainable chemical industry. Nano‐electrochemistry offers valuable insights into the comprehension of electrochemical mechanisms and behaviors at the nanoscale, as opposed to complex ensemble systems. Despite the use of various analytical tools, such as nanopore technology and scanning probe microscopy, for nano‐electrochemical research, direct operando and high‐throughput spatially resolved electrochemical measurements remain challenging. Electrochemiluminescence (ECL) is an electrochemical reactions‐dependent luminescence process without external light sources. Coupled with a microscopy configuration, a novel imaging methodology ECL microscopy (ECLM), is developed. ECLM, due to its distinctive imaging mode, holds considerable potential in the field of nano‐electrochemistry. This review will initially present an overview of the basic principles of ECL. The next section will describe the design of the ECLM apparatus and discuss its diverse applications in nano‐electrochemistry. Finally, the challenges and outline of the prospects for further development of the ECLM technique will summarized.

Abstract 2D metal‐chalcogenide nanoplatelets (NPLs) exhibit promising photocatalysis properties due to their ultrathin morphology, high surface‐to‐volume ratio, and enhanced in‐plane electron transport mobility. However, NPLs, especially cadmium chalcogenides, encounter challenges in CO2 photoreduction due to insufficient solar energy utilization and fast recombination of photogenerated charge carriers. Defect engineering offers a potential solution but often encounters difficulties maintaining structural integrity, mechanical stability, and electrical conductivity. Herein, by taking two monolayers (2ML) CdSe NPLs as a model system, selenium (Se) vacancies confined in atomic layers can enhance charge separation and conductivity. A straightforward approach to create Se vacancies in various monolayers CdSe NPLs (2, 4, and 5ML) has been developed, enabling efficient CO2 photoreduction with a 4‐fold increase in CO generation compared to their defect‐free counterparts. Significantly, accounting for higher charge density and efficient carrier transport due to Se vacancies, defective 2ML CdSe NPLs (VSe‐2ML CdSe) exhibit CO evolution performance up to 2557.5 µmol g−¹ h−¹ with no significant decay over 5 h, which is an order of magnitude higher than that of common semiconductor catalysts. This study establishes a practical way to design advanced 2D semiconductor photocatalysts to achieve efficient CO2 photoreduction via defect engineering.