Correlating local structure and migration dynamics in Na/Li dual ion conductor Na5YSi4O12.

Na5YSi4O12 (NYSO) is demonstrated as a promising electrolyte with high ionic conductivity and low activation energy for practical use in solid Na-ion batteries. Solid-state NMR was employed to identify the six types of coordination of Na+ ions and migration pathway, which is vital to master working mechanism and enhance performance. The assignment of each sodium site is clearly determined from high-quality 23Na NMR spectra by the aid of Density Functional Theory calculation. Well-resolved 23Na exchangespectroscopy and electrochemical tracer exchange spectra provide the first experimental evidence to show the existence of ionic exchange between sodium at Na5 and Na6 sites, revealing that Na transport route is possibly along three-dimensional chain of open channel-Na4-open channel. Variable-temperature NMR relaxometry is developed to evaluate Na jump rates and self-diffusion coefficient to probe the sodium-ion dynamics in NYSO. Furthermore, NYSO works well as a dual ion conductor in Na and Li metal batteries with Na3V2(PO4)3 and LiFePO4 as cathodes, respectively.

Cortical Microhemorrhage Presentation of Small Vessel Primary Angiitis of the Central Nervous System.

OBJECTIVE: Primary angiitis of the central nervous system (PACNS) is a rare vasculitis restricted to the brain, spinal cord, and leptomeninges. This study aimed to describe the imaging characteristics of patients with small vessel PACNS (SV-PACNS) using 7 T magnetic resonance imaging (MRI). METHODS: This ongoing prospective observational cohort study included patients who met the Calabrese and Mallek criteria and underwent 7 T MRI scan. The MRI protocol includes T1-weighted magnetization-prepared rapid gradient echo imaging, T2 star weighted imaging, and susceptibility-weighted imaging. Two experienced readers independently reviewed the neuroimages. Clinical data were extracted from the electronic patient records. The findings were then applied to a cohort of patients with large vessel central nervous system (CNS) vasculitis. RESULTS: We included 21 patients with SV-PACNS from December 2021 to November 2023. Of these, 12 (57.14%) had cerebral cortical microhemorrhages with atrophy. The pattern with microhemorrhages was described in detail based on the gradient echo sequence, leading to the identification of what we have termed the "coral-like sign." The onset age of patients with coral-like sign (33.83 ± 9.93 years) appeared younger than that of patients without coral-like sign (42.11 ± 14.18 years) (P = 0.131). Furthermore, the cerebral lesions in patients with cortical microhemorrhagic SV-PACNS showed greater propensity toward bilateral lesions (P = 0.03). The coral-like sign was not observed in patients with large vessel CNS vasculitis. INTERPRETATION: The key characteristics of the coral-like sign represent cerebral cortical diffuse microhemorrhages with atrophy, which may be an important MRI pattern of SV-PACNS. ANN NEUROL 2024;96:194-203.

Achieving Remarkable Specific Mechanical Strength and Energy Absorption Capacity in SiC Nanowire Networks through Graded Structural Design.

Lightweight porous ceramics with a unique combination of superior mechanical strength and damage tolerance are in significant demand in many fields such as energy absorption, aerospace vehicles, and chemical engineering; however, it is difficult to meet these mechanical requirements with conventional porous ceramics. Here, we report a graded structure design strategy to fabricate porous ceramic nanowire networks that simultaneously possess excellent mechanical strength and energy absorption capacity. Our optimized graded nanowire networks show a compressive strength of up to 35.6 MPa at a low density of 540 mg·cm-3, giving rise to a high specific compressive strength of 65.7 kN·m·kg-1 and a high energy absorption capacity of 17.1 kJ·kg-1, owing to a homogeneous distribution of stress upon loading. These values are top performance compared to other porous ceramics, giving our materials significant potential in various engineering fields.

Dynamic Evolution and Reversibility of a Single Au25 Nanocluster for the Oxygen Reduction Reaction.

Ultrasmall metallic nanoclusters (NCs) protected by surface ligands represent the most promising catalytic materials; yet understanding the structure and catalytic activity of these NCs remains a challenge due to dynamic evolution of their active sites under reaction conditions. Herein, we employed a single-nanoparticle collision electrochemistry method for real-time monitoring of the dynamic electrocatalytic activity of a single fully ligand-protected Au25(PPh3)10(SC2H4Ph)5Cl22+ nanocluster (Au252+ NC) at a cavity carbon nanoelectrode toward the oxygen reduction reaction (ORR). Our experimental results and computational simulations indicated that the reversible depassivation and passivation of ligands on the surface of the Au252+ NC, combined with the dynamic conformation evolution of the Au259+ core, led to a characteristic current signal that involves "ON-OFF" switches and "ON" fluctuations during the ORR process of a single Au252+ NC. Our findings reinvent the new perception and comprehension of the structure-activity correlation of NCs at the atomic level.

Field Detection of Uranyl in Coastal Water of China Using a Portable Device via DNA Photocleavage.

The urgent need for field detection of uranium in seawater is 2-fold: to provide prompt guidance for uranium extraction and to prevent human exposure to nuclear radiation. However, current methods for this purpose are largely hindered by bulky instrumentation, high costs of developed materials, and severe matrix interferences, which limit their further application in the field. Herein, we demonstrated a portable and label-free strategy for the field detection of uranyl in seawater based on the efficient photocleavage of DNA. Further experiments confirmed the generation of ultraviolet (UV) light-induced reactive oxygen species (ROS), such as O2•- and •OH, which fragmented oligomeric DNA in the presence of uranyl and UV light. Detailed studies showed that DNA significantly enhances uranyl absorption in the UV-visible region, leading to the generation of more ROS. A fluorescence system for the selective detection of uranyl in seawater was established by immobilizing two complementary oligonucleotides with the fluorescent dye SYBR Green I. The strategy of UV-induced photocleavage offers high selectivity, excellent interference immunity, and high sensitivity for uranyl, with a detection limit of 6.8 nM. Additionally, the fluorescence can be visually detected using a 3D-printed miniaturized device integrated with a smartphone. This method has been successfully applied to the on-site detection of uranyl in seawater in 18 Chinese coastal cities and along the coast of Hainan Island within 3 min for a single sample. The sample testing and field analysis results indicate that this strategy has promising potential for real-time monitoring of trace uranyl in China's coastal waters. It is expected to be utilized for the rapid assessment of nuclear contamination and nuclear engineering construction.

VILLIN2 regulates cotton defense against Verticillium dahliae by modulating actin cytoskeleton remodeling.

The active structural change of actin cytoskeleton is a general host response upon pathogen attack. This study characterized the function of the cotton (Gossypium hirsutum) actin-binding protein VILLIN2 (GhVLN2) in host defense against the soilborne fungus Verticillium dahliae. Biochemical analysis demonstrated that GhVLN2 possessed actin-binding, -bundling, and -severing activities. A low concentration of GhVLN2 could shift its activity from actin bundling to actin severing in the presence of Ca2+. Knockdown of GhVLN2 expression by virus-induced gene silencing reduced the extent of actin filament bundling and interfered with the growth of cotton plants, resulting in the formation of twisted organs and brittle stems with a decreased cellulose content of the cell wall. Upon V. dahliae infection, the expression of GhVLN2 was downregulated in root cells, and silencing of GhVLN2 enhanced the disease tolerance of cotton plants. The actin bundles were less abundant in root cells of GhVLN2-silenced plants than in control plants. However, upon infection by V. dahliae, the number of actin filaments and bundles in the cells of GhVLN2-silenced plants was raised to a comparable level as those in control plants, with the dynamic remodeling of the actin cytoskeleton appearing several hours in advance. GhVLN2-silenced plants exhibited a higher incidence of actin filament cleavage in the presence of Ca2+, suggesting that pathogen-responsive downregulation of GhVLN2 could activate its actin-severing activity. These data indicate that the regulated expression and functional shift of GhVLN2 contribute to modulating the dynamic remodeling of the actin cytoskeleton in host immune responses against V. dahliae.

Central vein sign and trigeminal lesions of multiple sclerosis visualised by 7T MRI.

BACKGROUND: Although trigeminal nerve involvement is a characteristic of multiple sclerosis (MS), its prevalence across studies varies greatly due to MRI resolution and cohort selection bias. The mechanism behind the site specificity of trigeminal nerve injury is still unclear. We aim to determine the prevalence of trigeminal nerve involvement in patients with MS in a consecutive 7T brain MRI cohort. METHODS: This observational cohort originates from an ongoing China National Registry of Neuro-Inflammatory Diseases. Inclusion criteria were the following: age 18 years or older, diagnosis of MS according to the 2017 McDonald criteria and no clinical relapse within the preceding 3 months. Each participant underwent 7T MAGNETOM Terra scanner (Siemens, Erlangen, Germany), using a 32-channel phased array coil at Beijing Tiantan Hospital. T1-weighted magnetisation-prepared rapid acquisition gradient echoes, fluid-attenuated inversion recovery (FLAIR) and fluid and white matter suppression images were used to identify lesions. FLAIR* and T2* weighted images were used to identify central vein sign (CVS) within the trigeminal lesions. RESULTS: 120 patients underwent 7T MRI scans between December 2021 and May 2023. 19/120 (15.8%) patients had a total of 45 trigeminal lesions, of which 11/19 (57.9%) were bilateral. The linear lesions extended along the trigeminal nerve, from the root entry zone (REZ) (57.8%, 26/45) to the pontine-medullary nucleus (42.2%, 19/45). 26.9% (7/26) of the lesions in REZ showed a typical central venous sign. CONCLUSION: In this 7T MRI cohort, the prevalence of trigeminal nerve involvement was 15.8%. Characteristic CVS was detected in 26.9% of lesions in REZ. This suggests an inflammatory demyelination mechanism of trigeminal nerve involvement in MS.

Rapid Mass Conversion for Environmental Microplastics of Diverse Shapes.

Rivers have been recognized as the primary conveyors of microplastics to the oceans, and seaward transport flux of riverine microplastics is an issue of global attention. However, there is a significant discrepancy in how microplastic concentration is expressed in field occurrence investigations (number concentration) and in mass flux (mass concentration). Of urgent need is to establish efficient conversion models to correlate these two important paradigms. Here, we first established an abundant environmental microplastic dataset and then employed a deep neural residual network (ResNet50) to successfully separate microplastics into fiber, fragment, and pellet shapes with 92.67% accuracy. We also used the circularity (C) parameter to represent the surface shape alteration of pellet-shaped microplastics, which always have a more uneven surface than other shapes. Furthermore, we added thickness information to two-dimensional images, which has been ignored by most prior research because labor-intensive processes were required. Eventually, a set of accurate models for microplastic mass conversion was developed, with absolute estimation errors of 7.1, 3.1, 0.2, and 0.9% for pellet (0.50 ≤ C < 0.75), pellet (0.75 ≤ C ≤ 1.00), fiber, and fragment microplastics, respectively; environmental samples have validated that this set is significantly faster (saves ∼2 h/100 MPs) and less biased (7-fold lower estimation errors) compared to previous empirical models.

Nanopore sequencing for smear-negative pulmonary tuberculosis-a multicentre prospective study in China.

PURPOSE: In this prospective study, the diagnosis accuracy of nanopore sequencing-based Mycobacterium tuberculosis (MTB) detection was determined through examining bronchoalveolar lavage fluid (BALF) samples from pulmonary tuberculosis (PTB) -suspected patients. Compared the diagnostic performance of nanopore sequencing, mycobacterial growth indicator tube (MGIT) culture and Xpert MTB/rifampin resistance (MTB/RIF) assays. METHODS: Specimens collected from suspected PTB cases across China from September 2021 to April 2022 were tested then assay diagnostic accuracy rates were compared. RESULTS: Among the 111 suspected PTB cases that were ultimately diagnosed as PTB, the diagnostic rate of nanopore sequencing was statistically significant different from other assays (P < 0.05). Fleiss' kappa values of 0.219 and 0.303 indicated fair consistency levels between MTB detection results obtained using nanopore sequencing versus other assays, respectively. Respective PTB diagnostic sensitivity rates of MGIT culture, Xpert MTB/RIF and nanopore sequencing of 36.11%, 40.28% and 83.33% indicated superior sensitivity of nanopore sequencing. Analysis of area under the curve (AUC), Youden's index and accuracy values and the negative predictive value (NPV) indicated superior MTB detection performance for nanopore sequencing (with Xpert MTB/RIF ranking second), while the PTB diagnostic accuracy rate of nanopore sequencing exceeded corresponding rates of the other methods. CONCLUSIONS: In comparison with MGIT culture and Xpert MTB/RIF assays, BALF's nanopore sequencing provided superior MTB detection sensitivity and thus is suitable for testing of sputum-scarce suspected PTB cases. However, negative results obtained using these assays should be confirmed based on additional evidence before ruling out a PTB diagnosis.

Clostridium lamae sp. nov., a novel bacterium isolated from the fresh feces of alpaca.

A novel Gram-positive, anaerobic, nonspore-forming, rod-shaped bacterium, designated strain NGMCC 1.200840 T, was isolated from the alpacas fresh feces. The taxonomic position of the novel strain was determined using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences revealed strain NGMCC 1.200840 T was a member of the genus Clostridium and closely related to Clostridium tertium DSM 2485 T (98.16% sequence similarity). Between strains NGMCC 1.200840 T and C. tertium DSM 2485 T, the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) were 79.91% and 23.50%, respectively. Genomic DNA G + C content is 28.44 mol%. The strain can utilise D-glucose, D-mannitol, D-lactose, D-saccharose, D-maltose, D-xylose, L-arabinose, D-cellobiose, D-mannose, D-melezitose, D-raffinose, D-sorbitol, L-rhamnose, D-trehalose, D-galactose and Arbutin to produce acid. The optimal growth pH was 7, the temperature was 37 °C, and the salt concentration was 0-0.5% (w/v). The major cellular fatty acids (> 10%) included iso-C15:0, anteiso-C15:0 and iso-C17:0 3-OH. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, three unidentified phospholipids and two unidentified aminolipids. Based on phenotypic, phylogenetic and chemotaxonomic characteristics, NGMCC 1.200840 T represents a novel species within the genus Clostridium, for which the named Clostridium lamae sp. nov. is proposed. The type strain is NGMCC 1.200840 T (= CGMCC 1.18014 T = JCM 35704 T).

Structural and Na-ion diffusion behavior of O3/P3/P2-type NaNi1/3Mn1/3Fe1/3O2 cathode for Na-ion batteries from first-principles study.

A layered sodium-ion battery cathode, O3/P3/P2-type NaNi1/3Mn1/3Fe1/3O2, has been systematically investigated by first-principles density functional theory to explore the detailed structural and Na-ion diffusion behavior during desodiation. Our results suggest that the (NaO6) spacing is greatest in the P3 phase and lowest in the O3 phase, with the P2 phase exhibiting intermediate spacing. During desodiation, the intermediate stages have a greater (NaO6) spacing than the initial and final stages. The great (NaO6) spacing facilitates the formation of the P3 phase, resulting in the structural evolution of NaxNi1/3Mn1/3Fe1/3O2 from the O3 to the P3 phase at x ≈ 0.59, finally reaching the O3 structure again at x ≈ 0.12. The electronic structure clearly proves that both Ni and Fe are active in O3/P3/P2-type NaxNi1/3Mn1/3Fe1/3O2. Ni2+ is oxidized to Ni3+ as Na content decreases from x = 1 to x = 0.66, then further oxidized to Ni4+ at x = 0.33, and finally, Fe3+ → Fe4+ oxidation occurs at x = 0. In the Na ion diffusion behavior, the order of the barrier is O3 (0.82 eV) > P2 (0.53 eV) > P3 (0.35 eV) at the initial stage, whereas it is O3 (0.53 eV) > P3 (0.21 eV) > P2 (0.16 eV) at a highly desodiated stage. The former can be traced back to the (NaO6) spacing, but the latter is related to the different Na sites. Our results thus provide a factor of the structural evolution and Na ion diffusion barrier by considering (NaO6) width and Na site changes during desodiation.

Ultrasound elasticity of diamond at gigapascal pressures.

Diamond is the hardest known material in nature and features a wide spectrum of industrial and scientific applications. The key to diamond's outstanding properties is its elasticity, which is associated with its exceptional hardness, shear strength, and incompressibility. Despite many theoretical works, direct measurements of elastic properties are limited to only ∼1.4 kilobar (kb) pressure. Here, we report ultrasonic interferometry measurements of elasticity of void-free diamond powder in a multianvil press from 1 atmosphere up to 12.1 gigapascal (GPa). We obtained high-accuracy bulk modulus of diamond as K0 = 439.2(9) GPa, K0' = 3.6(1), and shear modulus as G0 = 533(3) GPa, G0' = 2.3(3), which are consistent with our first-principles simulation. In contrast to the previous experiment of isothermal equation of state, the K0' obtained in this work is evidently greater, indicating that the diamond is not fully described by the "n-m" Mie-Grüneisen model. The structural and elastic properties measured in this work may provide a robust primary pressure scale in extensive pressure ranges.

HflX is a GTPase that controls hypoxia-induced replication arrest in slow-growing mycobacteria.

GTPase high frequency of lysogenization X (HflX) is highly conserved in prokaryotes and acts as a ribosome-splitting factor as part of the heat shock response in Escherichia coli. Here we report that HflX produced by slow-growing Mycobacterium bovis bacillus Calmette-Guérin (BCG) is a GTPase that plays a critical role in the pathogen's transition to a nonreplicating, drug-tolerant state in response to hypoxia. Indeed, HflX-deficient M. bovis BCG (KO) replicated markedly faster in the microaerophilic phase of a hypoxia model that resulted in premature entry into dormancy. The KO mutant displayed hallmarks of nonreplicating mycobacteria, including phenotypic drug resistance, altered morphology, low intracellular ATP levels, and overexpression of Dormancy (Dos) regulon proteins. Mice nasally infected with HflX KO mutant displayed increased bacterial burden in the lungs, spleen, and lymph nodes during the chronic phase of infection, consistent with the higher replication rate observed in vitro in microaerophilic conditions. Unlike fast growing mycobacteria, M. bovis BCG HlfX was not involved in antibiotic resistance under aerobic growth. Proteomics, pull-down, and ribo-sequencing approaches supported that mycobacterial HflX is a ribosome-binding protein that controls translational activity of the cell. With HflX fully conserved between M. bovis BCG and M. tuberculosis, our work provides further insights into the molecular mechanisms deployed by pathogenic mycobacteria to adapt to their hypoxic microenvironment.

Resilient and Antipuncturing Si3N4 Nanofiber Sponge.

Ceramic nanofibrous nanostructure-based sponges have attracted significant attention due to ultrahigh porosity, low thermal conductivity, large specific area, and chemical stability. From the regulation of the fiber itself to the construction method of 3D networks, efforts are being made to improve the mechanical properties of ceramic sponges for practical applications. So far resilient compressibility has been realized in ceramic nanofibrous-based sponges via structural design, but they still show brittle fracture under a more complex stress state. Herein, we introduced a highly aligned and interwoven Si3N4 nanofiber sponge, which exhibits superflexibility, large break elongation (>80%), large-strain reversible stretch (20%), and good resistance to tensile fatigue. The ceramic sponge also displays reversible compressibility up to 60% strain, puncture resistance, high air filtration efficiency (>99.8%), and low pressure drop (38% of cotton fiber), making the ceramic sponge a high-performance wearable respirator to protect us from harm due to PM2.5 pollution and possible microorganisms.

Selection and Mechanism Study of Q-Markers for Xanthocerais lignum Anti-Rheumatoid Arthritis Based on Serum Spectrum-Effect Correlation Analysis.

OBJECTIVE: To elucidate the chemical profile of Xanthocerais lignum's extracts of different polarities and their impact on rheumatoid arthritis (RA), we identified anti-RA markers and predicted their action mechanisms. METHODS: A collagen-induced arthritis rat model was established, and UPLC-Q-Exactive Orbitrap MS technology was employed to analyze and identify the chemical constituents within the alcohol extract of Xanthocerais lignum and its various extraction fractions, as well as their translocation into the bloodstream. Serum spectrum-effect correlation analysis was utilized to elucidate the pharmacodynamic material basis of Xanthocerais lignum against RA and to screen for Q-Markers. Finally, the potential anti-RA mechanisms of the Q-Markers were predicted through compound-target interaction data and validated using molecular docking techniques. RESULTS: We identified 71 compounds, with flavan-3-ols and flavanones as key components. Of these, 36 were detected in the bloodstream, including 17 original and 19 metabolized forms. Proanthocyanidin A2, dihydroquercetin, catechin, and epicatechin (plus glucuronides) showed potential anti-RA activity. These compounds, acting as Q-Markers, may modulate ERK, NF-κB, HIF-1α, and VEGF in the HIF-1 pathway. CONCLUSIONS: This research clarifies Xanthocerais lignum's pharmacodynamic material basis against RA, identifies 4 Q-Markers, and offers insights into their mechanisms, aiding quality assessment and lead compound development for RA treatment.

Identification of high oxygen-consuming substances in stormwater drainage systems illicitly connected with sewage system.

The dissolved oxygen content in water is an important indicator for assessing the quality of the water environment, and maintaining a certain amount of dissolved oxygen is essential for the healthy development of the ecological environment. When a water body is anoxic, the activity of anaerobic microorganisms increases and organic matter is decomposed to produce a large number of blackening and odorizing substances, resulting in black and odorous water bodies, which is a very common and typical phenomenon in China. Presently, there is still a relatively universal occurrence of illicitly connected stormwater and sewage pipes in the urban drainage pipe network in China, which makes oxygen-consuming substances be directly discharged into rivers through stormwater pipes and consume the dissolved oxygen in the water bodies, resulting in an oxygen deficiency of the water. This induces seasonal or year-round black and stink phenomena in urban rivers. Hence, identifying high oxygen-consuming substances, which lays the foundation for the subsequent removal of oxygen-consuming substances, is essential. Through a series of comparisons of water quality indicators and analysis of organic characteristics, it was found that the oxygen consumption capacity of domestic sewage was higher than that of industrial wastewater in the selected area of this study, and the oxygen-consuming substances of domestic sewage were small molecular amino acids. By comparing 20 conventional free amino acids, it was found that seven of them consumed oxygen easily, and compared with chemical oxygen consumption, biological oxygen consumption was in a leading position.

Synergistic Photoredox/Palladium Catalyzed Enantioconvergent Carboxylation of Racemic Heterobiaryl (Pseudo)Halides with CO2.

Herein, we report a synergistic photoredox/palladium catalytic system for the efficient enantioconvergent synthesis of axially chiral esters from racemic heterobiaryl (pseudo)halides (bromides/triflates) with CO2 and alkyl bromides under mild conditions. A wide range of axially chiral esters were obtained in good to high yields with excellent enantioselectivities. Detailed mechanistic studies unveiled that the ratio of photocatalyst and palladium catalyst exhibited significant impact on the chemo- and enantioselectivities of the reaction. Kinetic studies and control experiments supported the proposed mechanism involving cascade asymmetric carboxylation followed by SN2 substitution. The achievement of high enantioselectivity relies not only on the choice of synergistic metallaphotoredox catalysts but also on the utilization of alkyl bromides, which trap the generated chiral carboxylic anions in situ, thus preventing their immediate racemization.

Protein-Directed Au(0)-Rich Gold Nanoclusters as Ratiometric Luminescence Sensors for Auric Ions via Comproportionation-Induced Emission Enhancement.

Gold nanoclusters (Au NCs) are widely used as fluorescent probes in biomedical sensing and imaging due to their versatile optical properties and low cytotoxicity. Surface engineering of gold nanoclusters (Au NCs) aims to design a surface with versatile physicochemical performances, but previous investigations have primarily focused on the acquisition of the "brightest" species. This has resulted in other types of Au NC being neglected. In the present study, our group prepared a series of Au NCs that were rich in surface Au(0), using the "aged" form of bovine serum albumin (BSA) via controlling the pH during synthesis. We found that slight increases of alkalinity during synthesis over that which produced Au NCs with the most intensive photoluminescence generated the "darkest" Au NCs, which exhibited the strongest absorption. These Au NCs included more Au atoms and had a higher Au(0) content. Furthermore, the addition of Au3+ quenched the emission of the "brightest" Au NCs, but increased that of the "darkest" Au NCs. The increased Au(I) proportion observed in the Au3+-treated "darkest" Au NCs resulted in a novel comproportionation-induced emission enhancement effect, which we utilized to construct a "turn-on" ratiometric sensor for toxic Au3+. The addition of Au3+ generated simultaneous, opposite effects on blue-emissive diTyr BSA residues and red-emissive Au NCs. After optimization, we successfully constructed ratiometric sensors for Au3+ with high sensitivity, selectivity, and accuracy. This study will inspire a new pathway to redesign the protein-framed Au NCs and analytical methodology via comproportionation chemistry.

Zirconium-Directed Supramolecular Self-Assembly of Coenzyme A@GNCs with Enhanced Phosphorescence for Developing Ultrasensitive Tracer Probe of Dipicolinic Acid, a Biomarker of Bacterial Spores.

Luminescent gold nanoclusters (GNCs) are a class of attractive quantum-sized nanomaterials bridging the gap between organogold complexes and gold nanocrystals. They typically have a core-shell structure consisting of a Au(I)-organoligand shell-encapsulated few-atom Au(0) core. Their luminescent properties are greatly affected by their Au(I)-organoligand shell, which also supports the aggregation-induced emission (AIE) effect. However, so far, the luminescent Au nanoclusters encapsulated with the organoligands containing phosphoryl moiety have rarely been reported, not to mention their AIE. In this study, coenzyme A (CoA), an adenosine diphosphate (ADP) analogue that is composed of a bulky 5-phosphoribonucleotide adenosine moiety connected to a long branch of vitamin B5 (pantetheine) via a diphosphate ester linkage and ubiquitous in all living organisms, has been used to synthesize phosphorescent GNCs for the first time. Interestingly, the synthesized phosphorescent CoA@GNCs could be further induced to generate AIE via the PO32- and Zr4+ interactions, and the observed AIE was found to be highly specific to Zr4+ ions. In addition, the enhanced phosphorescent emission could be quickly turned down by dipicolinic acid (DPA), a universal and specific component and also a biomarker of bacterial spores. Therefore, a Zr4+-CoA@GNCs-based DPA biosensor for quick, facile, and highly sensitive detection of possible spore contamination has been developed, showing a linear concentration range from 0.5 to 20 µM with a limit of detection of 10 nM. This study has demonstrated a promising future for various organic molecules containing phosphoryl moiety for the preparation of AIE-active metal nanoclusters.

Fully Integrated Ratiometric Fluorescence Enrichment Platform for High-Sensitivity POC Testing of Salivary Cancer Biomarkers.

The point-of-care (POC) testing of cancer biomarkers in saliva with both high sensitivity and accuracy remains a serious challenge in modern clinical medicine. Herein, we develop a new fully integrated ratiometric fluorescence enrichment platform that utilizes acoustic radiation forces to enrich dual-emission sandwich immune complexes for a POC visual assay. As a result, the color signals from red and green fluorescence (capture probe and report probe, respectively) are enhanced by nearly 10 times, and colorimetric sensitivity is effectively improved. When illuminated using a portable UV lamp, the fluorescence color changing from red to green can be clearly seen with the naked eye, which allows a semiqualitative assessment of the carcinoembryonic antigen (CEA) level. In combination with a homemade smartphone-based portable device, cancer biomarkers like CEA are quantified, achieving a limit of detection as low as 0.012 ng/mL. We also directly quantify CEA in human saliva samples to investigate the reliability of this fully integrated platform, thus validating the usefulness of the proposed strategy for clinical diagnosis and home monitoring of physical conditions.