A Golgi apparatus-targeted ratiometric fluorescent probe for HOCl and its applications for anti-inflammatory evaluation of Dachengqi Decoction

Verifying the fluctuations of reactive oxidative species in the Golgi apparatus (GA) is crucial to investigate the pathology in inflammation. In this work, we present a fluorescent probe GA-PBC based on the phenothiazine-coumarin chromophore with a benzenesulfonamide unit as the GA target. GA-PBC manifests a red fluorescence peak at 620 nm, while it shifts to 510 nm upon reaction with HOCl, thus facilitating a ratiometric sensing manner. The probe shows high selectivity, superb sensitivity (limit of detection: 85.8 nM), rapid response (within seconds), and predominant accumulation in the GA. Intracellular imaging tests demonstrates the ability of GA-PBC to indicate the concentration changes of HOCl in live cells. Especially, it can be utilized to identify the active ingredients of Dachengqi Decoction (a kind of Traditional Chinese Medicine formula) in inflamed cells using HOCl in the GA as biomarker, suggesting that this probe is potentially useful for the evaluation of anti-oxidation efficacy of natural medicine.

Designing potent plasmonic Ag/TiO2 nanohetero-phase junction for visible light driven photo-catalysis and anti-bacterial effect

In this study, we have reported the impact of well-grown Ag nanoparticles on TiO2 nanofiber mat, focusing the efficiency in anti-bacterial properties with ROS generation. Herein, the nanoheterostructure sample was achieved using electrospinning technique, followed by a solvothermal approach. The core focus was based on the effect of growth of Ag nanoparticles by varying the solvothermal time as well as the molar weight of Ag precursor against both the anti-bacterial property with gram-negative (e.g. E. coli) and another gram-positive (e.g. E. faecalis) bacterium. Prior to the detailed anti-bacterial test, the morphological analysis and the heterojunction formation was thoroughly investigated which showed the clear growth of Ag nanoparticles upon altering the experimental parameters via HRTEM analysis. The investigation showed that superior antibacterial activity was exhibited for the higher Ag loaded heterojunction samples whereas there showed no effect in the absence of Ag nanoparticles for TiO2 nanofibers. This is basically due to the presence of higher superoxide radicals in the nanoheterojunction materials, which is proved by a systematic study using the NBT degradation test under dark and visible light environment. Moreover, this phenomenon can be elucidated by the surface plasmon resonance effect in Ag nanoparticles, which when illuminated under visible light generates electrons and is transferred to the conduction band of TiO2. This transfer promotes the generation of reactive oxygen species (ROS), resulting in the exceptional antibacterial properties observed in AgT-10 ˃ AgT-5 ˃ AgT-2.5 ˃ TiO2NF.

Efficient energy phosphorescence transfer and reversible phosphorescence in aromatic heterocyclic doped systems for advanced information storage

Organic room-temperature phosphorescent (RTP) materials have garnered significant attention in recent years due to their unique advantages, including diverse molecular structures, excellent biocompatibility, and favorable processability. Aromatic heterocyclic groups are known to effectively promote intersystem crossing (ISC), leading to a wide range of applications in this field. In this study, dibenzo[a,c]phenazin-11-yl(phenyl)methanone (DPM) was used as an energy acceptor, doped with the host material benzophenone (BP) and its derivatives (BP-R) as energy donors. After simple mixing and thorough mechanical grinding of both the host and guest components, photophysical process such as Phosphorescence resonance energy transfer (PRET) was activated, resulting in RTP emission. The doped system exhibited efficient golden-yellow phosphorescent emission with a phosphorescence lifetime of 196 ms and quantum yield of 30.5 %. Surprisingly, the DPM@PMMA film exhibits a gold-colored room-temperature phosphorescent emission and can be switched "on" and "off" with reversible phosphorescence by exposing the film to acidic and alkaline gases. Notably, the phosphorescent emission properties remain stable after multiple cycles. This doping system is further applied to various methods of information storage and encryption, highlighting its potential for multi-scenario applications.

Photo-responsive color/fluorescence efficient dual-switching properties of diarylethene modified Eu-doped ZnO@Silane quantum dots

Photo-responsive switches are very promising materials due to their potential applications in many fields. However, photo-controlled color/fluorescence dual-switching with higher modulation efficiency has rarely been reported. Herein, two new optical responsive switches were constructed by Eu-doped ZnO@Silane quantum dots (Eu:ZnO@Silane QDs) and two diarylethenes. The two switches exhibited strong fluorescence intensity and excellent photochromic properties due to the doping of Eu and the diarylethene modification on the surface of the QDs. The switches showed outstanding photo-controlled color/fluorescence dual-switching performance with UV/Vis lights irradiation. Although the structure of the two diarylethenes affected the fatigue resistance of the two switches, their fluorescence modulation efficiency (FME) could reach 100%. Furthermore, the two switches were successfully applied to bioimaging, and provide an alternative way for the design and construction of novel efficient color/fluorescence dual-switching.

An efficient coumarin-based thiosemicarbazone probe for ratiometric fluorescent sensing of Zn2+ and application in live cell imaging

Selective recognition of Zn2+ in biological and environmental samples is a challenge. An N, N-diethyl substituted coumarin thiosemicarbazone was designed as a fluorogenic sensor, HADICIT, [(E)-2-(1-(7-(diethylamino)-2-oxo-2H-chromen-3-yl)ethylidene)-N-isopropylhy drazine-1-carbothioamide] for the detection of Zn2+ to address the issue. The compound was characterized using FTIR, 1H NMR, 13C NMR, and mass spectrometry methods. The fluorogenic probe produces a selectively enhanced red-shift emission response in solution upon the addition of Zn2+ compared to other competing metal ions. The optical and fluorescence titration experiments suggest a 2:1 binding ratio of HADICIT to Zn2+, with an association constant of 3.33 × 106 M-1. The limit of detection (LoD) of HADICIT is found to be 86 nM, which is much below the WHO recommended standards in environment samples. Frontier molecular orbital calculations suggest intra-ligand charge transfer (ILCT) transitions. Cell imaging on HEK 293 cells using HADICIT indicates that the probe can detect Zn2+ ions in live cells.

A sensitive fluorescent probe for monitoring hypochlorous acid levels in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease. Hypochlorous acid (HClO) is a signature reactive oxygen species (ROS) closely associated with the progression of RA. Here, we report a novel fluorescent probe, ZCP1, which exhibits high sensitivity to HClO. In the presence of HClO, ZCP1 demonstrates a rapid detection time of 20 s and a low detection limit of 19.1 nM, allowing for fast and sensitive reactions with HClO, with a 150-fold fluorescence enhancement. ZCP1 can be employed for fluorescent detection of both exogenous and endogenous HClO levels in live cells. Furthermore, ZCP1 has been utilized to detect endogenous HClO in a mouse model of RA. This work provides a reliable tool for monitoring endogenous HClO both in vivo and in vitro, offering significant potential for future biological and pathological studies related to HClO.

Split T7 switch-based orthogonal logic operation of fluorogenic RNA aptamer for small molecules detection

Recent advances in fluorescent biosensors have stimulated the development of molecular detection. We herein developed a new orthogonal logic operation of fluorescent biosensor with cell-free to accomplish the detection of atrazine (ATZ) and tetrachlorobiphenyls (PCB77). The transcriptional process to generate fluorescent RNA aptamers (Mango) was controlled by molecules-probe bindings, which regulate split T7 promoter transcription switches ON or OFF. Leveraging the rapid in vitro T7 transcription process and high signal-to-background ratio of the Mango-TO1-Biotin complex, this biosensor demonstrates remarkable sensitivity in detecting ATZ and PCB77, with detection limit of 1.56 pM and 10.2 pM. Moreover, the orthogonality of four logic gates (AND, NOR, INHIBT, NIMPLY) were utilized the ATZ and PCB77 as input to construct, which could be activated by utilizing the target probe-driven association. The output of the fluorescence signal was controlled by split/intact fluorescent RNA aptamer (Mango) to achieve flexible and sensitive orthogonal operations. Significantly, the development of two-input logic gates has enabled the modular detection of various small molecules, offering a promising approach to intelligent multi-input analysis. Predictably, with the advantages of sensitivity, flexibility and easy-to-operate, this orthogonal logic gate platform holds immense potential in small molecules detection.

Investigation on the interaction between catalase and typical phthalates with different side chain lengths

Phthalates (PAEs), a category of plasticizers released from plastic products, have been widely detected in various environmental media and pose potential ecological risks to humans. Although the exposure risks of PAEs to organisms have been studied, the differences in the interactions between PAEs with different side chain lengths and biomolecules remain poorly understood at molecule levels. In this study, three commonly used PAEs (dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP)) were employed to investigate the influence of their side chain lengths on interactions with catalase (CAT), a key antioxidant enzyme. The effects of PAEs on CAT enzyme activity and their interaction mechanisms were investigated using multi-spectral technique and molecular docking techniques. The results indicate that the order of reduced enzyme activity by PAEs is DMP > DEP > DBP, which inversely correlates with the alkyl chain length of PAEs. Molecular docking analysis reveal that DBP failing to bind to the central cavity of CAT likely contributes to its minimal impact on enzyme activity. The multiple spectrums demonstrate that the binding affinity of PAEs to CAT and the changes of CAT conformational structure align with the observed decline in enzyme activity as alkyl chain length increased. Since enzyme activity ties to its structure, the structural alterations in CAT induced by PAEs would inevitably affect its functional expression in vivo. This study offers a comprehensive assessment on the possible toxicity of PAEs with different side chain lengths at the molecular levels, providing insights into their ecological risks.

A novel dual-function peptide-based fluorescent probe with large Stokes shift for the simultaneous detection and quantification of Ag(I) and Hg(II) ions

Achieving highly selective detections of Ag+ and Hg2+ is of great importance because their excessive emission can cause many diseases. Herein, a novel large Stokes shift fluorescent probe DKT based on dansyl fluorophore modified peptide biomolecules (NH2-Thr-Lys-Thr-NH2) was successfully synthesized, which can simultaneously detect Ag+ (turn on) and Hg2+ (turn off) based on different fluorescent response patterns in 100% aqueous solution. DKT also enables quantitative detection of Ag+ and Hg2+ with LODs of 37.1 nM and 26.7 nM, respectively. Besides, ESI-HRMS spectra, Job's plot, and fluorometric titration confirmed that the binding stoichiometry was determined to be 2: 1 between DKT and Ag+/Hg2+. Moreover, DKT has good fluorescence stability and rapidly detected Ag+ and Hg2+ over a wide pH range. Furthermore, DKT was applied to quantitative detect Ag+ and Hg2+ in three actual water samples, three tea samples and watermelon juice, which exhibited that DKT has good potential for accuracy in environmental monitoring and water quality control. Additionally, the results of fluorescence bioimaging showed that DKT had significant distinguishing ability to detect Ag+ and Hg2+ in living cells and zebrafish larvae. More importantly, smartphone App platform based on DKT not only provided a reliable new method for the field quantitative monitoring of Ag+ and Hg2+, but also expanded its application prospect in the field of heavy metal ions pollution detection.

Mesoporous Cu2O coated Au/Ag plasmonic nanocomposites as SERS sensing platform for ultrasensitive detection

Surface enhanced Raman scattering (SERS) is a suited detection technique for trace and ultrasensitive detection that extends even to single molecule levels. However, SERS application is currently limited by three main factors: 1) how to create more hotspots to enhance the sensitivity of SERS; 2) how to enrich trace target molecules in SERS hotspots; and 3) how to maintain the stability and reproducibility of SERS detection under environmental interference. In this study, mesoporous Cu2O coated Au/Ag plasmonic nanocomposites (NCs) were designed and prepared as SERS substrates. The tightly packed Au/Ag nanoaggregates (NAs) create more hotspots, oxygen vacancies in Cu2O can also enhances Raman signal by photoinduced charge transferring. Meanwhile, mesoporous Cu2O coating is beneficial for enriching more target molecules, so the as-prepared Au/Ag@Cu2O NCs showed excellent SERS sensitivity. When the target molecules 4-mercaptobenzoic acid (4-MBA) was detected on the Au/Ag@Cu2O substrate, the substrate showed high SERS activity. The enhancement factor reached as high as 3.78 × 106, and the detection limit was as low as 10-11 M. Meanwhile, the SERS spectra demonstrate excellent selectivity and reproducibility. In addition, the Au/Ag@Cu2O NCs substrate was applied to detect volatile organic compounds (VOC) pyridine molecules in the air, and when it was naturally adsorbed in air for 20 min, it showed an obvious SERS signal of pyridine. Therefore, these Au/Ag@Cu2O NCs with high SERS detection performance have important practical value in applications of volatile organic gas molecule.

Simultaneous microextraction of Brilliant Blue FCF, Malachite Green, and Rhodamine B in children's play materials: Assessment of greenness approach

The types, quantities, and permissible limits of dyestuffs used in the toy industry are susceptible since the relevant audience is children. For this reason, the dyestuffs used in children's play materials are one of the crucial issues to be emphasized. Rhodamine B, Brilliant Blue FCF, and Malachite Green are some of the most commonly used dyestuffs, and they are also included in our study. In addition to making play materials fun for children, it is vital to determine the amount of the dye in the play material to know the damage it will cause. For this purpose, an ultrasonically assisted, rapid, and highly sensitive green deep eutectic solvent-based microextraction method was developed to detect three synthetic dyes in different children's play materials. Extraction recoveries were between 92.8 and 103.2% under optimum conditions. The method was promising when the results obtained were compared with other studies. When additional recovery studies were carried out on different children's play materials, Rhodamine B in pink-coloured playdough and finger paint, Brilliant Blue FCF in blue-coloured playdough, finger paint, and watercolour paint, and Malachite green dyestuffs in finger paint and crayon were detected. In addition, this study is noteworthy as it is the first study in which simultaneous determination of three dyestuffs by high-performance liquid chromatography method was carried out.

MIL-101(Fe)-derived nickel-iron quasi-metal organic framework as efficient catalyst for oxygen evolution reaction

Metal-organic frameworks (MOFs) have emerged as promising precursors for the development of efficient non-noble metal electrocatalysts for oxygen evolution reaction (OER). Quasi-metal-organic frameworks, characterized by partially fractured connections between metal nodes and organic ligands, have attracted significant attention due to their large exposed active interfaces. To stimulate the development of quasi-MOF-based materials as OER catalysts, herein a Ni-Fe quasi-MOF catalyst was prepared through the pyrolysis of MIL-101(Fe) and subsequent ion exchange with Ni2+. The optimum catalyst MIL-101(Fe)350-Ni exhibits the lowest overpotential (290 mV) to achieve a current density of 10 mA cm-2, the smallest Tafel slope (89 mV dec-1) and the largest double-layer capacitance (0.268 mF cm-2). Furthermore, the current density drops only by ∼5 % (from 10 to 9.45 mA cm-2) after 20 h durability test. Experimental analysis suggests that the enhanced OER performance arises from the strong coupling effect between Fe and Ni, which improves the electron transfer efficiency and facilitates the active species generation. This work provide a feasible direction for constructing bimetallic quasi metal-organic frameworks to enhance the electrocatalytic OER performance and stability.

Metal-organic chelator frameworks for arsenic-based cancer treatment

The off-target toxicity of arsenic trioxide chemotherapy is a common Achilleś heel of metallodrugs. This limitation is usually mitigated by employing various cargo agents capable of transporting arsenic species to specific sites. More specifically, two of the most explored strategies to address arsenic trioxide's off-target toxicity include: (i) the complexation of As(III) species with chelating agents and (ii) their immobilization, either on the surface or, within non-porous and porous nanomaterials. In this work, we have explored the combination of mercaptosuccinic acid, an arsenic chelator, with zirconium oxo-clusters to assemble two new microporous Metal-Organic Frameworks (MOFs), denoted as BCM-1 and BCM-2 (BCM referring to Basque Center for Materials, Applications & Nanostructures). The specific chemical and structural features of these news frameworks have enabled controlling the arsenic loading and release in different scenarios. Specifically, arsenic release accelerates under oxidative conditions due to the rupture of thiol-arsenic bonds, caused by the oxidation of -SH groups to -SO3 within the MOF. Additionally, in acidic conditions typical of cancer microenvironments, the framework itself disassembles, further facilitating arsenic release. The particle size and arsenic loading capacity of BCM-1 can be easily modulated by controlling the synthesis conditions. This strategy has led to the development of micrometric, nanometric and gel-like materials, whose chemical stability in acidic and biological relevant media has been duly assessed. Notably, arsenic release from nano-BCM-1 is able to reverse the growth curve of HeLa cancer cells in approximately 50 h. This discovery paves the way towards the use of metal-chelator organic molecules in assembling new MOF materials capable of controlling the cargo and release of metallodrugs under in-vivo conditions.

An insect-based bioelectronic sensing system combining flexible dual-sided microelectrode array and insect olfactory circuitry for human lung cancer detection

Early detection of lung cancer significantly enhances treatment outcomes, yet current screening methods are limited by accessibility, sensitivity, and cost. This study introduces a bioelectronic sensing platform that integrates the highly sensitive locust olfactory system with a flexible dual-sided microelectrode array (MEA), for robust, noninvasive, and label-free detection of volatile lung cancer biomarkers. Using an innovative folding-annealing fabrication technique and PEDOT:PSS surface functionalization, we developed flexible, dual-sided MEAs with high electrode densities of 463, 687, and 766 channels/mm2 across prototypes, maintaining low impedance (within 4 × 104 Ω). These MEAs demonstrated mechanical flexibility and stability, enabling direct insertion into locust brain tissue without mechanical reinforcement and facilitating precise recording of neural activity in the antennal lobe triggered by lung cancer-related volatile organic compounds (VOCs) from low concentration (1 ppm). Advanced dimensionality reduction techniques applied to the electrophysiological recordings identified distinct neural response patterns to each VOC biomarker and the complex "scent" emitted from various cell lines. Using high-dimensional population neuronal response analysis with a leave-one-trial-out approach, the platform achieved a 100 % classification success rate for unknown VOCs. Additionally, varying concentrations (ppm-ppb) of individual VOC biomarkers were detected and classified with an accuracy of 86 %. The system was further tested for its ability to detect and classify human lung cancer cell lines based on the unique "scent" of cultured cells, including two non-small cell lung cancer (NSCLC) and two small cell lung cancer (SCLC) types. Quantitative assessments demonstrated that the platform achieved a classification accuracy of 85 % across these cell lines. These results substantiate the platform's potential for enhancing clinical diagnostics through the accurate identification of lung cancer stages and cell types. By integrating biological sensory systems with advanced bioelectronics, this study introduces a novel and efficient approach to lung cancer biomarker detection. It provides a non-invasive, brain-based cancer screening method, offering an accessible and innovative solution for early lung cancer diagnosis.

Preservation processes of liquid nitrogen spray freezing technology on Sebastes schlegelii in two stages of freezing and frozen storage: Focusing on changes in water status, protein characterization, texture properties and volatile compounds

This study explored the preservation process of liquid nitrogen spray freezing (LNSF) technology for Sebastes schlegelii during freezing and frozen storage. The findings demonstrated that Sebastes schlegelii achieved optimal storage quality at -100 °C LNSF technology and -40 °C frozen storage conditions. The -100 °C LNSF group exhibited water holding capacity and water migration patterns closest to the control group, maintaining firm fish texture and myogenic fiber integrity by decresing ice crystal formation by 39.40 %. Furthermore, it suppressed the synthesis of fishy odors and irritants substances, such as heptanal, nonanal and sulfur ethers. The -40 °C frozen storage maintained stable texture, significantly decreasing lipid oxidation and the degradation and aggregation of myofibrillar proteins (MP). This process also preserved protein spatial structure and muscle integrity while minimizing flavor changes. The results indicated that LNSF technology has significant potential to enhance the quality of Sebastes schlegelii.

A tumor heterogeneity-independent antigen-responsive nanocarrier enabled by bioorthogonal pre-targeting and click-activated self-immolative polymer

Bioorthogonal pre-targeting alleviate the limitations of traditional nanomedicines in passive and active targeting delivery. However, the high selectivity of bioorthogonal pre-targeting depends on the high expression level of antigens in lesion sites, and there are very limited targets with sufficient overexpression. Herein, we propose a tumor heterogeneity-independent antigen-responsive nanocarrier utilizing bioorthogonal pre-targeting and click-activated self-immolative polymers for stimulus signal conversion and amplification. This approach comprises a tetrazine (Tz) conjugated with trastuzumab (T-Tz), and a bioorthogonally activatable nanocarrier CONP which self-assembled by isocyanide and polyethylene glycol-modified poly (thiocarbamate) (NC-PTC-PEG) and hydrogen sulfide (H2S)-responsive self-immolative polymers. In practice, T-Tz is first injected to actively pretarget HER2-positive tumor cells and followed by the second injection of nanocarrier CONP. The NC-PTC-PEG in CONP undergoes a click reaction with Tz to generate H2S, thereby achieving the transformation from antigen signal to H2S signal. Finally, NO2-PTC-PEG responds to H2S stimulation and undergoes a head-to-tail depolymerization process similar to dominoes to produce a large amount of H2S, further amplifying the stimulus signal. This bioorthogonal pre-targeting combine with click-activated self-immolative polymers is anticipated to enhance the effectiveness of existing pre-targeting strategies for tumor imaging and therapy, with the potential to overcome challenges posed by tumor heterogeneity.

Aptamer-modified GSH-degradable honokiol polyprodrug nanoparticles for ovarian cancer-specific targeting therapy

Honokiol (HK) is a polyphenol isolated from the Magnolia genus, a component of traditional Chinese herbal medicine, which can effectively suppress the growth of various tumors, including ovarian cancer. However, its low water solubility and lack of tumor-targeting ability have greatly hindered the clinical application of HK. Herein, a glutathione (GSH)-sensitive HK polyprodrug was prepared using HK as the backbone. An EpCAM-specific aptamer and poly(ethylene glycol) (PEG) were then conjugated to the HK polyprodrug, and the resulting polyprodrug was assembled into nanoparticles (NPs) in water. The HK polyprodrug-formed NPs achieved high drug loading and GSH-responsive drug release. Moreover, after optimization, HK polyprodrug NPs (A/P-PHK NP40), formed by aptamer-modified and PEG-modified prodrug at a feed molar ratio of 2: 3, exhibited the highest ability to target EpCAM-overexpressing ovarian cancer cells. A/P-PHK NP40 also demonstrated a greater cell growth inhibition effect in ovarian cancer cells compared to free HK and control HK NPs. All in all, this work reported a novel strategy for HK delivery based on microenvironment responsiveness polyprodrug, which provided a potential method for ovarian cancer targeting therapy.

Electrodeposition of carbon nanotubes and conjugation of arginyl-glycyl-aspartic acid for the following of glioblastoma cells on bionanocomposites

The improvement of surface treatment methods that permit the tuning of cell adhesion on the surface of biomaterials and devices is of considerable importance. Here, multi-walled carbon nanotubes (MWCNT) were modified with 4-aminothiophenol (4ATP). Then, electrodeposition of MWCNT-4ATP was carried out on 4ATP-modified screen-printed gold electrodes (SP-Au). After conjugation of Arginyl-glycyl-aspartic acid (RGD)-peptide on Poly(MWCNT-4ATP), the adhesion of U-87MG glioblastoma cells was examined by differential pulse voltammetry (DPV) technique. The synthesized MWCNT-4ATP and the obtained Poly(MWCNT-4ATP)/RGD surfaces were characterized using Scanning Electron Microscopy-Energy Dispersive X-Ray Spectrometer (SEM-EDS), Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR), X-Ray Photoelectron Spectrometer (XPS). The linear range for U-87MG glioblastoma cells was 102-106 cells/mL. The developed Poly(MWCNT-4ATP)/RGD cell adhesion platform provided monitoring of U-87MG glioblastoma cells using DPV technique and fluorescent imaging.

Red-emitting fluorescent probe with excellent water solubility for the in situ monitoring of endogenous H2S in wheat under salt and Al3+ stress

Hydrogen sulfide (H2S) is a pivotal signaling molecule in plants and appropriate levels are essential for normal growth. As such the real-time detection of H2S in plants is required since it enables timely targeted interventions. However, most fluorescent probes for detecting H2S reported to date exhibit fluorescence quenching in aqueous solution thereby significantly constraining their potential for in vivo applications. In response to this challenge, we present a natural flavylium-inspired fluorescent probe with robust water solubility for turn-on detection of H2S in organisms. The probe exhibits a remarkable 28-fold turn-on signal at 619 nm with rapid reaction kinetics (-20 min), coupled with high sensitivity (LOD = 0.37 μM) and exceptional selectivity for H2S. By employing the probe as an imaging agent, we managed to successfully visualize the fluctuations of exogenous and endogenous H2S levels in HeLa cells. More importantly, the probe enabled the facile and precise visualization of H2S in stressed wheat roots, achieving remarkable micron-level resolution through in-situ imaging, thereby confirming the upregulation of H2S in response to aluminum ion and salt stress. Our research provides a novel tool to investigate the response and mitigation mechanisms of H2S in plants under diverse stress conditions, as well as strategies for enhancing crop resilience.

Impact of graphene oxide functionalized with nano-magnetite on swine wastewater anaerobic treatment

This study evaluated the impact of graphene oxide functionalized with nano-magnetite (GO-Fe3O4) on the anaerobic treatment of swine wastewater (SW). The experiment was conducted in glass reactors with 200 mL of reaction volume, operating in fed-batch mode in three treatment cycles, each with 35 days. The evaluated doses of GO-Fe3O4 were 3 mg L-1 (1 mg gVSS-1) and 150 mg L-1 (50 mg gVSS-1). In the third cycle, GO-Fe3O4 (150 mg L-1) increased the biochemical methane potential by 17 %, the biogas production potential by 18 %, the methane production rate constant by 31 %, the maximum methane production rate by 32 %, and reduced the lag phase time by 25 %. Potential direct interspecies electron transfer partners are Midas g 156 and Clostridium sensu stricto 1 with Methanobacterium beijingense and Methanothrix soehngenii. GO-Fe3O4 is a powerful and unique material for improving methane and biogas production via SW anaerobic treatment.

Simulated sunlight-enhanced peroxymonosulfate activation via S-scheme BiOBr/g-C3N4 aerogel heterojunction for multi-pollutant remediation: Band structure and interface engineering

The intricate composition of real-world aquatic systems significantly constrains the improved overall performance of powder catalysts, meanwhile their recyclability is inferior to the bulk counterparts (e.g. aerogels). Herein, by loading BiOBr onto g-C3N4 nanosheets and combining them with agarose, an S-scheme heterojunction aerogel (abbreviated as BCA) was synthesized, whose structure was confirmed by the density functional theory calculation. Importantly, the BCA could activate peroxymonosulfate (PMS) under simulated sunlight for degrading multi-pollutant. And the BCA/PMS/Light system efficiently degraded various organic contaminants in aqueous environments, achieving a high degradation rate constant of 0.1503 min-1 for rhodamine B (RhB), significantly surpassing the performance of CA/PMS/Light (0.0378 min-1) and BCA/PMS (0.0763 min-1) systems. Free radical quenching experiment and electron paramagnetic resonance analysis reveal that 1O2, •O2-, •OH and SO4•- in the BCA/PMS/Light system were pivotal in RhB degradation, with a dominant non-radical mechanism. Additionally, Fukui function analysis pinpointed the primary reaction sites within the RhB molecule. The photocatalytic heterojunction aerogel exhibits outstanding stability, environmental sustainability and versatility, which can guide the development of simulated sunlight-driven PMS activation for multi-pollutant degradation, catering for scalable water treatment applications.

Phase-engineered metal boride nanobeads for highly efficient oxygen evolution

Non-precious metals with tailored phase structures show promise as oxygen evolution reaction (OER) catalysts due to their high inherent catalytic activity and extensive exposed active surface area. However, the mechanisms by which phase structures enhance catalytic performance remain unclear. Herein, we synthesized an amorphous cobalt boride (CoB) catalyst via a magnetic field-assisted method, yielding uniform nanoparticles that self-assemble into a nanobead structure. This material undergoes heat treatment to transition from an amorphous phase to a crystalline phase. The catalyst demonstrated exceptional OER activity and long-term stability in an alkaline electrolyte, requiring only 350 mV overpotential at 10 mA cm-2. The amorphous CoB demonstrates remarkable durability by maintaining stable operation for 100 h under harsh conditions characterized by high alkalinity and elevated temperature without any observable performance degradation. We demonstrate that electrochemical activation of an amorphous catalyst can unveil active sites within the bulk material, leveraging the short-range order characteristic of amorphous structures. This process significantly amplifies the active site density, consequently enhancing the electrocatalytic performance of the amorphous catalyst in the oxygen evolution reaction within water oxidation. Furthermore, in situ Raman spectroscopy reveals that amorphous CoB rapid self-reconstruction upon electrochemical activation, leading to the formation of a metal (oxy)hydroxide active layer. This study offers valuable insights into the design of high-efficiency OER catalysts by elucidating the mechanisms underlying amorphous and crystalline materials.

Manganese dioxide coupled metal-organic framework as mitophagy regulator alleviates periodontitis through SIRT1-FOXO3-BNIP3 signaling axis

Periodontitis is a prevalent chronic inflammatory disease characterized by alveolar bone resorption. Its progression is closely linked to oxidative stress where reactive oxygen species (ROS) generated by mitochondria exacerbate inflammation in positive feedback loops. Strategies for mitochondrial regulation hold potential for therapeutic advances. Metal-organic frameworks (MOFs) have shown promise as nanozymes for ROS scavenging. However, inability to directly regulate cellular processes to prevent further ROS production from damaged mitochondria during persistent inflammation makes MOFs insufficient in treating periodontitis. This study synthesizes MnO2@UiO-66(Ce) by introducing MnO2 within nanoscale mesoporous UiO-66 type MOFs. MnO2 coupled with Ce clusters in MOF channels, forms a superoxide dismutase/catalase cascade catalytic system. More importantnly, manganese endows the MOFs with bioactive effects which enhances mitophagy, facilitating the removal of damaged mitochondria, thereby restoring long-term cellular homeostasis. The results demonstrate that this synergistic antioxidant solution MnO2@UiO-66 restores mitochondrial homeostasis and osteogenic activity of periodontal ligament cells in vitro and alleviates inflammatory bone resorption in a ligature-induced periodontitis model in vivo. The SIRT1-FOXO3-BNIP3 signaling axis plays a key role in this process. This study may provide a design strategy that combines a highly efficient cascade catalytic system with long-term regulation of cellular homeostasis to combat oxidative stress in chronic inflammation.

12-Hydroxyoctadecanoic acid forms two kinds of supramolecular gels in nanostructured protic ionic liquids

HYPOTHESIS

We postulate that the amphiphilic nanostructure of ionic liquids, consisting of interpenetrating networks of polar and apolar domains, may enable them to support distinct self-assembled organogel-like and hydrogel-like structures.

EXPERIMENTS

The structures of gels formed by the low molecular weight gelator 12-hydroxystearic acid (12HSA) and its ammonium salts have been investigated from the molecular to the microscale by a combination of powder X-ray diffraction, SAXS/WAXS, FTIR, CD, and optical microscopy, together with rheological characterisation of the gels formed.

FINDINGS

12HSA is shown to form long-lived ionogels in ethylammonium and propylammonium nitrate ionic liquids at low concentrations via two distinct mechanisms; supramolecular, hydrogen-bond driven aggregation of the acid and amphiphilic assembly of the conjugate base. 12HSA gel structures were shown to consist of high aspect-ratio twisted crystalline fibrils assembled from H-bonded dimers, similar to organogels, while 12HS salts form an elongated rectangular ribbon of solvophobically-associated lamellar stacks with an opposite twist to the acid form. Partial neutralisation of 12HSA gels with base can generate coexisting mixtures of both types of gel in these ILs.

Boosting catalytic reduction of hexavalent chromium over PdNi alloy by electron injection into unoccupied Pd d-band

Hexavalent chromium (Cr(VI)) in industrial wastewater presents a severe environmental threat. Using formic acid for Cr(VI) reduction offers an efficient and sustainable chromium remediation. While Pd reduces the energy barrier for formic acid dissociation to produce H*, the formation of strong PdH bonds hinders subsequent Cr(VI) reduction due to elevated energy levels and an increased proportion of unoccupied states in the Pd 4d bands. To address this challenge, we developed a PdNi/TiO2 nanofibrous catalyst designed to optimize hydrogen adsorption through intermetallic electron transfer within the alloy. Experimental and theoretical results confirm that electrons from Ni are injected into the unoccupied portion of the Pd d-band, downshifting the d-band center upon alloy formation. This electron injection optimizes the electronic states of the Pd active sites, lowering the energy barrier for formic acid dissociation while weakening the PdH interaction, thereby facilitating the release of H* species. The optimized Pd6Ni4/TiO2 achieves an improved turnover frequency (TOF) of 164.8 min-1 for Cr(VI) reduction, outperforming most previous Pd-based catalysts.

Insight into the Facilitated surface reconstruction of NiFe layered double hydroxide by constructing heterostructures with Prussian blue analogues for enhanced oxygen evolution reaction

The dynamic surface electrochemical reconstruction of electrocatalysts in alkaline media for oxygen evolution reaction (OER) has been extensively documented, especially for layered double hydroxides (LDHs). However, there remines a limited understanding on how to effectively promote electrochemical reconstruction towards the desired highly active oxyhydroxide surface,which is crucial for enhancing the OER performance. The NiCo-PBA/NiFe LDH heterostructured catalyst was successfully synthesized by a one-step hydrothermal method. The incorporation of Prussian blue analogues (PBAs) was found to significantly promote the surface depth reconstruction of NiFe LDH, achieving a much higher degree of reconstruction compared to the natural electrochemical activation. In-situ Raman spectroscopy, various ex-situ characterizations, and density functional theory (DFT) calculations reveal that the introduction of PBAs intensifies the dissolution-reconstruction process and facilitates phase transition to form high-valent oxyhydroxide structures with optimized electron transfer pathways. The reconstructed NiCo-PBA/NiFe LDH-Re100 demonstrates exceptional electrocatalytic activity and long-term durability during the OER process. This study provides novel insights into the design of heterostructured catalysts and highlights their significant potential for applications in efficient electrocatalysis.

Photo-assisted synthesis of ternary metal (oxy)hydroxide electrode for enhanced seawater splitting and solar-to-hydrogen conversion

Seawater electrolysis offers a sustainable route for large-scale hydrogen production, yet the development of non-noble metal electrocatalysts with high activity and chloride resistance remains challenging. Here, we report a photo-assisted synthesis method to fabricate a ternary metal (oxy)hydroxide electrocatalyst (p-S-Ni(Fe,Co)OOH) from nickel foam, utilizing photogenerated holes to achieve atomic-level Fe/Co co-doping. The p-S-Ni(Fe,Co)OOH exhibits bifunctional activity in alkaline seawater, requiring overpotentials of 108 and 186 mV for hydrogen- and oxygen-evolution reactions (HER and OER) at 10 mA cm-2 in 1.0 M KOH, respectively, outperforming its dark-synthesized counterpart (S-Ni(Fe,Co)OOH). When integrated into a photovoltaic-electrocatalytic (PV-EC) powered by commercial Si solar cells, p-S-Ni(Fe,Co)OOH achieves solar-to-hydrogen (STH) efficiencies of 13.2 % (simulated seawater) and 12.1 % (natural seawater), with stable operation over 30 h. Density functional theory (DFT) calculations identify Fe as the primary active site for OER, while Fe/Co co-doping modulates the Fe d-band center toward the Fermi level, optimizing intermediate adsorption energetics and improving chloride resistance. This study proposes a synthesis strategy for seawater-compatible catalysts elucidates electronic structure modulation at colloidal interface.

Monosolvent system for high-purity lead-free perovskite precursors scalable synthesis based on solubility differences

Metal halide perovskites (MHPs) are promising materials for various optoelectronic applications due to their unique properties. However, the presence of lead (Pb) in MHPs raises environmental and health concerns, prompting the search for lead-free alternatives. This study introduces a universal strategy for synthesizing high-purity lead-free perovskite precursors through a methanol monosolvent system that utilizes solubility differences. The synthesis method is scalable and universal, applicable to five lead-free perovskites such as Cs2SnCl6, Cs2TeCl6, Cs3Sb2Cl9, Cs2ZnCl4, and Cs2SnBr6, all maintaining high structural and compositional integrity with purities exceeding 99.985 %. The Cs2SnCl6 perovskite precursors achieve a high yield of 91.7 %. The synthesized Cs2SnCl6 perovskite exhibits superior electron mobility and lower baseline resistance when incorporated into gas sensors, demonstrating a high response (1.98 at 20 ppm) for dimethyl carbonate (DMC) detection due to its high purity. The simplicity and effectiveness of this one-step synthesis method offer a significant advancement for the production of high-quality perovskite materials for commercial applications in sensors and optoelectronics.

Pre-carbonization-mediated construction of urchin-like NiFe2O4 superparticles with enhanced CNT growth for efficient oxygen evolution

In this study, we report the rational design and synthesis of carbonized NiFe2O4 superparticles (CarSPs) hierarchically integrated with densely aligned carbon nanotube (CNT) architectures, hereafter denoted as CarSP-CNTs, which exhibit a biomimetic urchin-like morphology. Through exploitation of the colloidal self-assembly and catalytic functionalities inherent to NiFe2O4 nanoparticles (NPs), we achieve seamless integration of one-dimensional CNT arrays with three-dimensional superstructural frameworks. Systematic investigation reveals that the pre-carbonization of surface-bound organic ligands coupled with subsequent CNT growth induces synergistic interplay between conductive carbon matrices and active spinel oxide phases. This structural optimization confers CarSP-CNTs with enhanced charge transfer kinetics and catalytically robust interfaces, as evidenced by their superior electrocatalytic performance for the oxygen evolution reaction (OER) in alkaline electrolyte (1 M KOH). The optimized CarSP-CNTs exhibit a minimal overpotential of 307 mV to deliver a current density of 10 mA cm-2, alongside remarkable operational stability exceeding 20 h of continuous electrolysis. These findings establish a paradigm for the rational design of hierarchically structured, multi-component electrocatalysts through coordinated nanoscale engineering, offering a versatile platform for advancing energy conversion technologies.

The potential of metal-organic framework MIL-101(Al)-NH2 in the forefront of antiviral protection of cells via interaction with SARS-CoV-2 spike RBD protein and their antibacterial action mediated with hypericin and photodynamic treatment

The global pandemic of SARS-CoV-2 has highlighted the necessity for innovative therapeutic solutions. This research presents a new formulation utilising the metal-organic framework MIL-101(Al)-NH2, which is loaded with hypericin, aimed at addressing viral and bacterial challenges. Hypericin, recognised for its antiviral and antibacterial efficacy, was encapsulated to mitigate its hydrophobicity, improve bioavailability, and utilise its photodynamic characteristics. The MIL-101(Al)-NH2 Hyp complex was synthesised, characterised, and evaluated for its biological applications for the first time. The main objective of this study was to demonstrate the multimodal potential of such a construct, in particular the effect on SARS-CoV-2 protein levels and its interaction with cells. Both in vitro and in vivo experiments demonstrated the effective transport of hypericin to cells that express ACE2 receptors, thereby mimicking mechanisms of viral entry. In addition, hypericin found in the mitochondria showed selective phototoxicity when activated by light, leading to a decrease in the metabolic activity of glioblastoma cells. Importantly, the complex also showed antibacterial efficacy by selectively targeting Gram-positive Staphylococcus epidermidis compared to Gram-negative Escherichia coli under photodynamic therapy (PDT) conditions. To our knowledge, this study was the first to demonstrate the interaction between hypericin, MIL-101(Al)-NH2 and the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein, which inhibits cellular uptake and colocalises with ACE2-expressing cells. Therefore, the dual functionality of the complex - targeting the viral RBD and the antibacterial effect via PDT - emphasises its potential to mitigate complications of viral infections, such as secondary bacterial infections. In summary, these results suggest that MIL-101(Al)-NH2 Hyp is a promising multifunctional therapeutic agent for antiviral and antibacterial applications, potentially contributing to the improvement of COVID-19 treatment protocols and the treatment of co-infections.

Metal-organic framework Cr-MIL-101-assisted synthesis of highly dispersed chromium oxide incorporated silica for efficient n-hexane dehydrogenation to n-hexenes

Mesoporous CrOx-SiO2 with highly dispersed chromium sites was synthesized by encapsulating silica into the metal-organic framework Cr-MIL-101 for the dehydrogenation of n-hexane. The optimal SiO2 content is 27.1 wt% for CrOx-SiO2 catalyst, where the octahedral structure of Cr-MIL-101 is preserved, Cr atoms are uniformly distributed, a large specific surface area (395 m2/g) is obtained, and abundant surface oxygen vacancies are observed. 89.7 wt% selectivity to n-hexenes and 28.9 wt% n-hexane conversion are achieved on the CrOx-27.1wt%SiO2 catalyst in the absence of H2. The characterization and in-situ experimental results reveal that the proper distance between the active chromium sites (16.7 Cr/nm2 based on the highly dispersed Cr atoms) on the CrOx-27.1wt%SiO2 catalyst is responsible for the high n-hexenes selectivity. This critical distance depends on the (i) molecular size and (ii) adsorption geometry of n-hexane, (iii) structural properties of the catalyst. The specially designed redox reaction and density functional theory calculation (DFT) at active oxidative chromium sites show that chromium sites accompanied by oxygen vacancies exhibit high dehydrogenation activity for n-hexane conversion. This work gives a novel idea to synthesis high-performance dehydrogenation catalyst for n-hexane and long-chain alkanes.

Nanotherapeutic strategies exploiting biological traits of cancer stem cells

Cancer stem cells (CSCs) represent a distinct subpopulation of cancer cells that orchestrate cancer initiation, progression, metastasis, and therapeutic resistance. Despite advances in conventional therapies, the persistence of CSCs remains a major obstacle to achieving cancer eradication. Nanomedicine-based approaches have emerged for precise CSC targeting and elimination, offering unique advantages in overcoming the limitations of traditional treatments. This review systematically analyzes recent developments in nanomedicine for CSC-targeted therapy, emphasizing innovative nanomaterial designs addressing CSC-specific challenges. We first provide a detailed examination of CSC biology, focusing on their surface markers, signaling networks, microenvironmental interactions, and metabolic signatures. On this basis, we critically evaluate cutting-edge nanomaterial engineering designed to exploit these CSC traits, including stimuli-responsive nanodrugs, nanocarriers for drug delivery, and multifunctional nanoplatforms capable of generating localized hyperthermia or reactive oxygen species. These sophisticated nanotherapeutic approaches enhance selectivity and efficacy in CSC elimination, potentially circumventing drug resistance and cancer recurrence. Finally, we present an in-depth analysis of current challenges in translating nanomedicine-based CSC-targeted therapies from bench to bedside, offering critical insights into future research directions and clinical implementation. This review aims to provide a comprehensive framework for understanding the intersection of nanomedicine and CSC biology, contributing to more effective cancer treatment modalities.

A multifunctional trap-capture-kill antibacterial system for enhanced wound healing via modified decellularized mushroom aerogels

Wound infections are prevalent and can result in prolonged healing times. In this study, we referred to the "trap-capture-kill" antibacterial strategy to create a wound dressing (DS/PDA@GO-L) by coupling graphene oxide (GO) with lysine and coating it onto the decellularized mushroom stem (DS) using polydopamine (PDA). The mechanism of action of the bacteria-killing process involves lysine chemotaxis and the siphoning effect of DS aerogel, with the process of killing the bacteria being initiated via near-infrared photothermal treatment. In vitro studies demonstrated that DS/PDA@GO-L exhibited excellent blood and cell compatibility, while in vivo experiments revealed its remarkable efficacy in combating bacterial infections. Specifically, the combination of DS/PDA@GO-L with photothermal therapy led to the elimination of over 95 % of S. aureus, E. coli, and Pseudomonas aeruginosa. Furthermore, the aerogel, when used in conjunction with photothermal therapy, significantly reduced bacterial infection at the wound site and accelerated wound healing. During the wound's proliferative phase, it notably enhanced vascularization and extracellular matrix deposition. Furthermore, immunohistochemical staining revealed that bacterial clearance led to a reduction in pro-inflammatory responses and a decrease in the expression of pro-inflammatory cytokines, thereby restoring the wound's inflammatory environment to a pro-regenerative state. Taken together, the developed DS/PDA@GO-L holds great potential in the field of infected skin wound healing.

Detection of doxycycline via a smartphone-assisted ratiometric fluorescence platform with cerium‑nickel bimetallic nanoclusters

The accumulation of tetracycline antibiotics, such as doxycycline (DOX), in animal-derived foods poses considerable health risks to humans when found in excessive concentration levels. This research introduces a ratiometric fluorescence sensor for the detection of DOX utilizing ovalbumin-stabilized cerium‑nickel bimetallic nanoclusters (OVA-Ce/Ni NCs). The sensor exploits the sensitizing effect of ovalbumin on DOX, resulting in a fluorescence peak at 510 nm, while its inherent blue fluorescence at 420 nm gradually quenches. Under optimal conditions, the OVA-Ce/Ni NCs sensor exhibited a linear response range of 0.2-80 μM for DOX, with an exceptionally low detection limit of 51 nM. The sensor exhibited excellent selectivity for DOX and was successfully applied for the detection of DOX in milk and fish samples. Furthermore, smartphone-assisted detection facilitated visual identification of DOX. This study demonstrates a highly sensitive and selective approach for detecting DOX in animal-derived foods, with potential implications in pollutant identification and control.

Confining metal nanoparticles and nanoclusters in covalent organic frameworks for biosensing and biomedicine

Metal nanoscale particles, primarily including metal nanoparticles (MNPs) and nanoclusters (MNCs), have garnered substantial interests owing to their unique electronic configurations and distinct physicochemical properties. However, practical applications are frequently constrained by their limited stability and aggregation tendency. Covalent organic frameworks (COFs), featuring highly ordered periodic architectures, have emerged as ideal porous matrices for hosting metal nanoparticles. The resulting metal-embedded COFs synthesized through adsorption methods (M/COFs) or in-situ reduction (M@COFs) not only mitigate nanoparticle aggregation and enhance stability but also demonstrate synergistic effects that generate enhanced or novel functionalities, significantly broadening their application potential. This review firstly examines adsorption-based synthesis strategies for M/COFs through physical and chemical approaches. Subsequently, we analyze in-situ reduction methods for M@COFs, categorizing them by reduction pathways: deposition, impregnation-pyrolysis, and "one-step" synthesis. Special attention is given to an emerging pore wall engineering strategy within in-situ reduction approach. The biosensing and biomedical applications of metal-embedded COFs are systematically examined, highlighting their comparative advantages over conventional nanomaterials in sensing and antimicrobial applications. While metal-embedded COFs remain in their developmental infancy and face considerable challenges, the controlled synthesis of multifunctional variants promises transformative potential across biomedical domains.

An electrochemical biosensing platform initiated simultaneously from multi-directions with programmable enzyme-free strategy for DNA variant detection

Single-nucleotide variations (SNVs) represent vital clinical and biological information in the onset and progression of many cancers, but lacking of cost-effective, high-sensitive and reliable SNVs detection method. In this study, we propose a programmable electrochemical biosensing strategy initiated simultaneously from multi-directions by enzyme-free amplifying circuit for high-sensitivity SNVs detection. Through elaborate design, we utilized the power of conventional enzyme-free catalytic reaction to activate a multidirectional initiation self-assembly process, enabling multiple amplification. This innovative cascade strategy significantly improved the amplification performance and detection sensitivity. Subsequently, KRAS gene of cancer cells was used as proof-of concept model for SNVs recognition to demonstrate the capability. With the help of cascade design, the single-base differences between SNV sequence and wild-type sequence (WT) could be differentiated and amplified effectively. Consequently, abundant Y-shaped DNA structure efficiently was induced by DNA variant to generate on the electrode surface, facilitating the incorporation of methylene blue (MB) redox indicator. Therefore, a "signal-on" electrochemical biosensing platform was constructed. Our enzyme-free biosensor achieved a low detection limit of 36 aM and a broader linear range spanning from 100 aM to 1 nM under optimal experimental conditions. The capability of proposed cascaded DNA network to detect DNA variants in complex cancer cells and serum samples indicated the potential applicability in real sample analysis.

Innovative approaches in bioadhesive design: A comprehensive review of crosslinking methods and mechanical performance

In biomedical applications, bioadhesives have become a game-changer, offering novel approaches to tissue engineering, surgical adhesion, and wound healing. This comprehensive review paper provides a thorough analysis of bioadhesives and their categorization according to application site and crosslinking process, bonding efficacy, and mechanical characteristics. The use of bioadhesives to stop bleeding and seal leaks is also covered in the review. The article delves into the various crosslinking techniques used in bioadhesives, including chemical, physical, and hybrid approaches. It emphasizes on how these mechanisms control the adhesive's elasticity, durability, and structural integrity. In addition, the review looks at the mechanical strength of bioadhesives, taking important characteristics like shear strength, toughness, elasticity, and tensile strength into account. It is highlighted how important bioadhesives are to the life sciences because they drive innovation and interdisciplinary cooperation, address present healthcare issues, and create new avenues for therapeutic development. The paper also explores some vital characteristics of bioadhesives that, when strategically combined with one another, improve their efficacy and usefulness in a variety of surgical and medical applications. The analysis concludes by examining nature-inspired adhesives, including those based on geckos, mussels, and tannic acid, and their unique bonding mechanisms and potential for use in advanced biomedical applications.

A double network composite hydrogel with enhanced transdermal delivery by ultrasound for endometrial injury repair and fertility recovery

Endometrial injury and resulting female infertility pose significant clinical challenges due to the notable shortcomings of traditional treatments. Herein, we proposed a double network composite hydrogel, CSMA-RC-Zn-PNS, which forms a physical barrier on damaged tissue through photo-crosslinking while enabling sustained release of the active ingredient PNS. Based on this, we developed a combined strategy to enhance transdermal delivery efficiency using ultrasound cavitation. In vitro experiments demonstrated that CSMA-RC-Zn-PNS exhibits excellent biosafety, biodegradability, and promotes cell proliferation, migration, and tube formation, along with antioxidant and antibacterial properties. In a rat endometrial injury model, the ultrasound cavitation effect was demonstrated to enhance transdermal delivery efficiency, and the ability of CSMA-RC-Zn-PNS to promote endometrial regeneration, anti-fibrosis and fertility restoration was verified. Overall, this strategy combining CSMA-RC-Zn-PNS hydrogel and ultrasound treatment shows promising applications in endometrial regeneration and female reproductive health.

Co-doped Bi24O31Br10 with photoswitchable Br, O binary vacancies synergistically provide dynamic active sites for N2 reduction

Ultra-thin two-dimensional bismuth oxyhalide with rich surface vacancies is an ideal material for photocatalytic nitrogen reduction reaction (NRR) of ammonia synthesis. However, the repair of these vacancies during the reaction invalidates its unique local microenvironmental advantage as an active site. Herein, ultra-thin Co-doped Bi24O31Br10 (Co-BOB) nanosheets with photo-switchable Br, O binary vacancies were synthesized by a hydrothermal method. The surface Br and O vacancies were generated under light and filled again with migrated Br- and O in solution at air atmosphere under dark. The Br vacancies serve as a medium for electron accumulation and transfer facilitating interlayer charge transfer. The O vacancies generate charge delocalization and lead to the local electron-deficient site, which promotes the adsorption and activation of N2. In addition, density functional theory calculation show that N2 reduction follows an alternating association pathway producing ammonia on the surface of Co-BOB. The photogenerated vacancies reduce the energy barrier of the first proton-coupled electron transfer process acting as a rate-determining step. The ammonia production rate of 5 % Co-BOB is 120.3 µmol g-1 h-1, which is 6.23 times higher than initial BOB. Meanwhile, the unique photoswitchable protection mechanism ensures the excellent recyclability of Co-BOB. Experiments and calculations reveal the role of formation of photoswitchable Br, O binary vacancies on Co-BOB nanosheets for efficient and stable NRR performance. This work provides a new strategy for promoting sustainable NRR by combining photoswitchable facilitated reaction with the active site regeneration.

Interface-tailored iridescent nanocellulose films with retentive antifouling and recyclable multi-environmental responsive properties

Cellulose nanocrystals (CNCs) with distinctive chiral nematic structures and attractive iridescent structural color after evaporation-induced-assembly have induced much interest. However, the hydrophilic nature and rigidity of CNCs materials greatly hindered their application in various environmental conditions. Herein, nature-derived xylose (Xyl) was introduced to regulate the chiral nematic structure of CNCs so as to improve their mechanical strength and flexibility. Facile solvent immersion strategy of materials in hydrophobic 1H,1H,2H,2H-Perfluorodecyltriethoxysilane (C16H19F17O3Si, PFDTS) solution with various concentration was performed to endow hydrophobicity, as well as remaining their original cholesteric arrangements of the nanoparticles. Chemical and morphological characterizations proved the well distribution and intercalation of Xyl and PFDTS molecules into the chiral structures. The films after tailored interfacial modification exhibited satisfying hydrophobicity with highest water contact angle of ∼ 103°, and retentive anti-fouling capabilities were achieved for the films. Moreover, repeatable and highly sensitive humidity and acid response via iridescent change was fulfilled, well maintaining high mechanical strength (∼70 MPa) after recycling. Besides, excellent biocompatibility was confirmed for the modified materials via cell viability (>90 %) determination. Therefore, the proposed chiral CNCs-based hydrophobic films may greatly widen the application of cellulosic nanomaterials in areas of electrical devices, environmental protection and biomedical treatments, etc.

Manipulating the Li/Ni/Fe mixed configuration promotes structure stability of Li-rich layered oxides

Lithium-rich layered oxides (LLOs) are highly promising for applications in Li-ions batteries as the cathode materials due to their high energy density. However, LLOs often suffer from significant capacity and voltage loss due to the instability of the layered structure when in the deep extraction state. This inherent instability poses a considerable challenge to their practical application. Herein, a distinctive Li/Ni/Fe mixed configuration was constructed by using the exchange mechanism of Fe ions with Li and Ni ions in the Li layer. This configuration not only improves structural stability, but also expands the layer spacing to accelerate Li+ diffusion. Density functional theory (DFT) calculations indicate that the presence of Li/Ni/Fe mixed configuration leads to more Li - O - Li configurations and decreasing the characteristic energy gap above the Fermi energy level. This configuration also effectively increases the migration energy barrier of transition metal (TM) ions and oxygen (O) vacancy formation energy, which reducing the irreversible migration of TM ions and the escape of O. The target material exhibits high-capacity retention of 82.1 % after 300 cycles at 1C, accompanied by a minimal voltage fading rate of just 0.33 mV/cycle. This study offers innovative strategies to enhance the stability of LLOs, facilitating their widespread commercial use.

Cobalt-glycerolates derived Co@C-T catalysts for the catalytic transfer hydrodeoxygenation of lignin-derived vanillin

The hydrodeoxygenation of lignin-derived bio-oil is the key to its upgrading into biofuels. Currently, the catalytic transfer hydrodeoxygenation (CTHDO) has been widely studied due to the avoidance of the use of hydrogen gas. In this work, cobalt-glycerolates nanospheres derived Co@C-T catalysts were synthesized via the solvothermal method, followed by the carbothermic method at different calcination temperatures in a nitrogen atmosphere. The obtained Co@C-450 catalyst exhibited the best vanillin CTHDO performance and afforded nearly 100 % conversion of vanillin and 87 % yield of 2-methoxy-4-methylphenol (MMP) under the conditions of 140 °C, 1 MPa N2 and 3 h using isopropanol as H-donor. Based on the various characterizations, the Co@C-450 catalyst possessed the appropriate metallic Co0 sites, acid sites (Co(II)), and carbon defects, and the high catalytic activity was attributed to the synergistic effects of them. During the CTHDO process, the Co0 sites were responsible for carbonyl hydrogenation of vanillin to generate 4-(hydroxymethyl)-2-methoxyphenol (HMP) and the generation of active hydrogen species from isopropanol, while the acid sites (Co(II)) were responsible for the cleavage of the CO bond in HMP to form MMP. In addition, the Co@C-450 catalyst had good applicability to other lignin-derived monomers, and its performance did not decrease after 11 runs. This work could provide some insights for upgrading bio-oil.

Waste corn stalk-derived biomass carbon materials as two-electron ORR electrocatalysts for dye contaminant degradation and water disinfection

Porous carbon materials as efficient two-electron oxygen reduction reaction (ORR) electrocatalysts for on-situ production of hydrogen peroxide (H2O2) is one of the promising alternatives to the traditional anthraquinone process. Herein, waste corn stalks-derived porous carbon composites (CSDC-O, Fe/CSDC-O-12) were developed as two-electron ORR electrocatalysts for H2O2 generation and the further organic dye pollutants degradation and water disinfection. The high-temperature pyrolysis and oxidation treatment enriched the hierarchical porous structure of the biomass carbon materials, improved graphitization degree and the content of oxygen-containing functional groups, which facilitated the increase of active sites density, the mass and charge transfer rates acceleration, and the active and selective H2O2 generation. Based on the remarkable two-electron ORR selectivity and long-term stability in both alkaline and acidic media exhibited by Fe/CSDC-O-12, it was used to completely degrade 25 mg L-1 of rhodamine B and methyl orange within 70 and 80 min, respectively. Moreover, the CSDC-O electrocatalyst demonstrated disinfection efficiency exceeding 99.9999 % against Escherichia coli and Staphylococcus aureus within 20 and 60 min, respectively. Thus, our work provides a feasibility verification for the transformation of abundant biomass corn stalk waste into low-cost, sustainable, and high-value-added two-electron ORR electrocatalysts, and expand their application in dye contaminant degradation and water disinfection.

Function sulfur nanodots for the detection and discrimination of allura red from food pigments

Detection and discrimination of allura red (AR) are highly desired for food safety, which is still challenging due to the abundant of food pigments and their minor differences in optical properties. Heren, we developed a fluorescence assay for quantitative detection and discrimination of AR utilizing the dual function of sulfur nanodots (S-dots), where S-dots acted as both the fluorescence indicator and the decomposition reagents for AR. The fluorescence of S-dots was quenched by AR and gradually recovered, attributed to the decomposition effects of S-dots and etched reagents. AR was detected as low as 5 nM, and discrimination of AR was realized through observing the fluorescence recovery. The detection and discrimination of AR in practical food samples were also realized, and a portable test kit was fabricated for the on-site detection of AR. The presented work provided a new clue for designing sensors, exhibiting application potential for guarantee food safety.

Simultaneous determination of thirteen related substances in lenalidomide API by a stability-indicating RP-HPLC method

The purpose of this study was to develop and validate a high performance liquid chromatography (HPLC) method for the separation and determination of related impurities and potential genotoxic impurity in the lenalidomide API. Chromatographic separation was performed on a Zorbax SB-AQ column (250 mm × 4.6 mm, 5 μm) at a wavelength of 220 nm using pH 4.0 phosphate buffer-acetonitrile as the mobile phase in gradient elution mode. The validation results demonstrate that the method has acceptable specificity, linearity, accuracy, precision and robustness. The detection limits and quantitation limits ranged from 2 to 17 ng/mL and from 6 to 50 ng/mL, respectively. A linear relationship was observed between the peak area and concentration of lenalidomide and impurities, with a correlation coefficient value of r ≥ 0.999. The formation and chemical structures of oxidation and base degradation products of lenalidomide have also been confirmed. The newly developed HPLC method is suitable for use in quality-control laboratories for qualitative and quantitative assessment of thirteen kinds of related substances in the lenalidomide API.

Highly sensitive and rapid screening of radical electrochemical intermediates by chemical labeling untargeted mass spectrometry

Capturing and analyzing low-abundance, short-lived, and unstable radical intermediates during electrochemical (EC) reactions is important for understanding EC reaction mechanisms. Herein, we developed a chemical labeling strategy for rapid screening and highly sensitive analysis of EC radical intermediates by mass spectrometry (MS). Taking 5,5-dimethyl-1-pyrroline N-oxide (DMPO) labeling reagent as an example, DMPO can react with radical intermediates to form stable labeling products with characteristic fragmentation daughter ions or neutral loss in tandem MS, so the labeled intermediates can be screened by precursor ions scan or neutral loss scan. Further combined with our recently established floating electrochemical electrospray mass spectrometry platform (FE-ESI-MS), we realized online confirmation and in-depth analysis of radical intermediates, and accelerated the study of EC reaction mechanisms. We established the strategy based on the labeling analysis of radical intermediates produced by EC oxidation of acetaminophen and a mixed EC reaction system containing 10 substrates, and further studied the radical-radical cross coupling mechanism of sodium p-toluenesulfinate and 2-methyl-2H-indazole. The labeled products not only improved the MS response by more than 10 times, but also exhibited typical fragmentation behavior, which contributed to the rapid screening of radical intermediates. This chemical labeling strategy will increase the capability of MS for finding important EC intermediates in untargeted analysis and further investigating low abundant and short-lived EC intermediates in the future.

A biodegradable, microstructured, electroconductive and nano-integrated drug eluting patch (MENDEP) for myocardial tissue engineering

We produced a microstructured, electroconductive and nano-functionalized drug eluting cardiac patch (MENDEP) designed to attract endogenous precursor cells, favor their differentiation and counteract adverse ventricular remodeling in situ. MENDEP showed mechanical anisotropy and biaxial strength comparable to porcine myocardium, reduced impedance, controlled biodegradability, molecular recognition ability and controlled drug release activity. In vitro, cytocompatibility and cardioinductivity were demonstrated. Migration tests showed the chemoattractive capacity of the patches and conductivity assays showed unaltered cell-cell interactions and cell beating synchronicity. MENDEP was then epicardially implanted in a rat model of ischemia/reperfusion (I/R). Histological, immunofluorescence and biomarker analysis indicated that implantation did not cause damage to the healthy myocardium. After I/R, MENDEP recruited precursor cells into the damaged myocardium and triggered their differentiation towards the vascular lineage. Under the patch, the myocardial tissue appeared well preserved and cardiac gap junctions were correctly distributed at the level of the intercalated discs. The fibrotic area measured in the I/R group was partially reduced in the patch group. Overall, these results demonstrate that MENDEP was fully retained on the epicardial surface of the left ventricle over 4-week implantation period, underwent progressive vascularization, did not perturb the healthy myocardium and showed great potential in repairing the infarcted area.

Efficient phosphorus doping strategy to overcome lattice distortion in Mn-based cathodes for advanced potassium-ion batteries

Manganese-based metal oxides have emerged as promising cathode materials for potassium-ion batteries (PIBs) due to favourable structural characteristics, such as large interlayer spacing and long diffusion paths for K+ ions. However, there are challenges due to the Jahn-Teller effect of the Mn3+ and the large volumetric strains of the charge/discharge process. In this study, the unfavorable lattice strains as well as the electrochemical properties were improved by phosphorus doped potassium manganate strategy. P-doped increases the K+ storage active sites by increasing the Mn3+ content to enhance the storage capacity. In addition, the PO4 and MnO6 octahedra share O to stabilize the lattice and suppress the Jahn-Teller effect as well as the bulk strain induced by K+ insertion/extraction. The reduced charge transfer resistance as well as the enlarged layer spacing help to reduce the K+ diffusion barrier, fast K+ diffusion kinetics, and improve the rate performance. K0.6MnP0.02O2 (P-KMnO-2) has capacity of 50.97 mAh g-1 at 1000 mA g-1. And after 500 cycles at 500 mA g-1, P-KMnO-2 still has capacity of 41 mAh g-1. In addition, maximum energy density of full cell composed of P-KMnO-2 and soft carbon reached 176.4 Wh kg-1.

Role of synergies of Cu/Fe3O4 electrocatalyst for nitric oxide reduction to ammonia

The electrochemical nitric oxide reduction reaction (NORR) is a promising green process for nitric oxide (NO) removal and ammonia (NH3) synthesis. Among existing catalysts, copper (Cu) exhibits relatively high activity but is less stable and does not provide enough *H to further increase the NH3 yield. In this study, a Cu/Fe3O4 electrocatalyst with synergistic catalysis was synthesized. Cu contributes to NO activation and sequential hydrogenation, while Fe3O4 promotes the decomposition of H2O to provide more *H and jointly promote NH3 synthesis. The Cu/Fe3O4 shows a high NH3 yield of 347.5 ± 5.9 μmol h-1 cm-2 at -0.5 V vs. RHE and high Faraday efficiency (FE) of 95.8 ± 0.4 %, superior to most reported non-precious metal catalysts. Moreover, the catalyst activity was not attenuate after the 100 h stability test. The aqueous Zn-NO battery system demonstrates concurrent energy generation and ammonia synthesis capabilities, delivering a peak power output of 9.53 mW cm-2 alongside efficient NH3 production with a yield of 595.7 ± 5.1 μg h-1 cm-2.

Chiral nanoassembly remodels tumor microenvironment through non-oxygen-dependent depletion lactate for effective photodynamic immunotherapy

Targeting lactate metabolism in tumor microenvironment (TME) has emerged as a promising strategy for enhancing immunotherapy. However, the commonly used strategy of lactate oxidation by lactate oxidase consumes oxygen, exacerbating tumor hypoxia and hindering immunotherapy. Here, we present a novel tumor-targeting, near infrared light-activated and TME-responsive chiral nanoassembly (Zn-UCMB) for enhancing photodynamic triggered immunogenic cell death (ICD) through a nonoxygen-dependent depletion of lactate. In the moderately acidic TME, the chiral Zn complex liberated from the Zn-UCMB selectively coordinates with l-lactate, leading to the depletion of lactate. Additionally, the Zn-UCMB facilitates the decomposition of H2O2 into O2, which significantly enhances the efficacy of photodynamic therapy (PDT) and triggers a robust ICD effect. Moreover, the nonoxygen-dependent depletion of lactate can reprogram the TME by reducing the expression of HIF-1α, decreasing VEGF expression, and mitigating immunosuppressive conditions. This prompts the phenotypic transformation of tumor-associated macrophages from M2 to M1. Consequently, Zn-UCMB not only enhances the efficacy of PDT but also elicits a potent ICD during 980 nm laser irradiation, thereby effectively suppressing tumor growth and metastasis. The findings offer a novel approach to overcome the limitations of existing lactate metabolism-targeting strategies and provide a promising therapeutic option for enhancing the efficacy of immunotherapy.