Physiological evaluation and transcriptomic and proteomic analyses to reveal the anti-aging and reproduction-promoting mechanisms of glycitein in Caenorhabditis elegans.

Soy isoflavones from soy sauce residues have important biological activities. However, the anti-aging and reproduction-promoting effects of glycitein are still rarely reported. Here, we systematically evaluated and explored the anti-aging and reproduction-promoting effects of glycitein in Caenorhabditis elegans (C. elegans). Firstly, we analyzed the effects of glycitein on the lifespan under normal and heat stress, reproduction, locomotion, and reactive oxygen species (ROS) levels of C. elegans. The results showed that 100 µmol L-1 glycitein increased the anti-stress ability of nematodes and activated the antioxidant defense system. Secondly, transcriptomic and proteomic technologies were further used to explore in-depth the anti-aging and reproduction-promoting mechanisms of glycitein in C. elegans. The results showed that both differentially expressed proteins (DEPs) including PDE-2 and MSRA-1 and differentially expressed genes (DEGs) including skpo-2 and cytochrome P450 (cyp-35A3, cyp-35A5, cyp-35C1, cyp-35D1) were associated with the extension of the lifespan and the exertion of antioxidant capacity. VIT-1, plx-2, and Y73F8A.35 were related to promoting reproduction. ASP-1, DNJ-10, and abu-1 were related to the anti-stress ability of glycitein. Pathway analysis revealed that the longevity regulation pathway and FOXO signaling pathway were regulated by the changes in genes and proteins to improve the lifespan of the nematode. Moreover, hydrogenase regulation, longevity regulation, and lipid metabolism were regulated by the changes in genes and proteins to promote the reproduction of nematodes. This study not only demonstrates a viable strategy for utilizing soy sauce residues, but also provides a theoretical foundation and developmental insights for the future application of glycitein.

Glow-type luminol chemiluminescence based on a supramolecular enhancer of cyclodextrin.

BACKGROUND: Chemiluminescence (CL) bioassay is one of the most advanced and used detection method in clinical diagnosis and biomedical research because of the advantages of low background, easy operation, and wide-field imaging without a light source or microscope. The luminol/hydrogen peroxide/horseradish peroxidase (luminol/H2O2/HRP) system is the most popular CL system, but its application in high-throughput imaging detection is challenged due to its low luminescence efficiency and flash-type emission which is difficult in ensuring the reproducibility and consistency of detection results. RESULTS: We reported a glow-type CL system of luminol@CD/H2O2/HRP by using a supramolecular enhancer of cyclodextrin (CD). This luminol@CD/H2O2/HRP system exhibited a luminescence lifetime of 41 min for sensitive and accurate imaging analysis. The long-lasting CL emission was attributed to the formation of a 1:1 host-guest complex between luminol and CD, which could stabilize the emitter and effectively reduce nonradiative relaxation. The formation of luminol@CD complex was determined through NMR experiments and theoretical analysis. Under optimum conditions, the luminol@CD/H2O2/HRP system showed higher sensitivity and much better precision than classical luminol/H2O2/HRP system for imaging detection of HRP. Especially, this glow-type luminol@CD/H2O2/HRP system realized CL imaging of microwell arrays on microfluidic chips. In addition, the luminol@CD/H2O2/HRP system was successfully applied for point-of-care detection of 17ß-estradiol based on a competitive mechanism of host-guest recognition. SIGNIFICANCE: An efficient CL system is crucial for obtaining reproducible and consistent results for accurate detection. Our luminol@CD/H2O2/HRP system emitted strong and persistent luminescence, resulting in reliability and efficiency at both CL macroscopic and microscopic imaging detection. We expected the luminol@CD/H2O2/HRP CL system to be applied in various detection fields.

Aggregation-Induced Electrochemiluminescence of Ir(ppy)3-Functionalized ZIF-8 for Microcystin-LR Detection via the trans-Cleavage Activity of CRISPR-Cas12a.

An efficient electrochemiluminescence (ECL) emitter, Ir(ppy)3-based molecules has recently been reported to exhibit aggregation-induced electrochemiluminescence (AIECL) phenomenon. However, it remains a significant challenge to control the aggregation states of these molecules and achieve uniform aggregates with intense ECL emission. In this work, a biosensor was developed to detect microcystin-LR (MC-LR) based on Ir(ppy)3-functionalized zeolitic imidazolate framework-8 (Ir-ZIF-8) as the ECL emitter and the trans-cleavage activity of CRISPR-Cas12a as the methodological strategy. The Ir-ZIF-8, a functional metal-organic framework (MOF), exhibited the AIECL phenomenon via the spatial domain-limiting effect of encapsulating Ir(ppy)3 into the mesopores of ZIF-8, while the porosity and highly ordered topological structure of ZIF-8 effectively limited the molecular motion of Ir(ppy)3. CRISPR-Cas12a was employed to indiscriminately cleave double-stranded DNA decorated with carboxy tetramethylrhodamine (TAMRA), which quenched the ECL signal of Ir-ZIF-8 by resonance energy transfer and then separated the quencher from Ir-ZIF-8 to reactivate the signal. The concentration of MC-LR was designed to correlate with both the quencher amount and the activity of Cas12a. Then, two linear regression equations for MC-LR detection were constructed to improve the accuracy of the biosensor, and the constructed biosensor showed remarkable reproducibility, stability, and selectivity. The accurate detection of MC-LR with limits of detection of 1.2 and 5.9 pg/mL was made possible by the high quenching efficiency of TAMRA and the effective cutting ability of the editable CRISPR-Cas12a system.

Correction: Physiological evaluation and transcriptomic and proteomic analyses to reveal the anti-aging and reproduction-promoting mechanisms of glycitein in Caenorhabditis elegans.

Correction for 'Physiological evaluation and transcriptomic and proteomic analyses to reveal the anti-aging and reproduction-promoting mechanisms of glycitein in Caenorhabditis elegans' by Jianping Lei et al., Food Funct., 2024, https://doi.org/10.1039/D4FO02271H.

Bioinspired Dual Hemin-Bonded G-Quadruplex and Histidine-Functionalized Metal-Organic Framework for Sensitive Biosensing.

Biomimetic enzymes have emerged as ideal alternatives to natural enzymes, and there is considerable interest in designing biomimetic enzymes with enhanced catalytic performance to address the low activity of the current biomimetic enzymes. In this study, we proposed a meaningful strategy for constructing an efficient peroxidase-mimicking catalyst, called HhG-MOF, by anchoring histidine (H) and dual hemin-G-quadruplex DNAzyme (double hemin covalently linked to 3' and 5' terminals of G-quadruplex DNA, short as hG) to a mesoporous metal-organic framework (MOF). This design aims to mimic the microenvironment of natural peroxidase. Remarkably, taking a terbium MOF as a typical model, the initial rate of the resulting catalyst was found to be 21.1 and 4.3 times higher than that of Hh-MOF and hG-MOF, respectively. The exceptional catalytic properties of HhG-MOF can be attributed to its strong affinity for substrates. Based on the inhibitory effect of thiocholine (TCh) produced by the reaction between acetylcholinesterase (AChE) and acetylthiocholine, a facile, cost-effective, and sensitive colorimetric method was designed based on HhG-MOF for the measurement of AChE, a marker of several neurological diseases, and its inhibitor. This allowed a linear response in the 0.002 to 1 U L-1 range, with a detection limit of 0.001 U L-1. Furthermore, the prepared sensor demonstrated great selectivity and performed well in real blood samples, suggesting that it holds promise for applications in the clinical field.

Low-potential anodic electrochemiluminescence of terbium metal-organic frameworks for selective microRNA-155 detection.

High excitation potential is recognized as a harmful factor for the biological activity of biomacromolecules, such as proteins and nucleic acids, in electrochemiluminescence (ECL) biosensing. Developing low-potential ECL luminophores is vital for improving ECL accuracy in actual sample sensing. In this work, based on porous metal-organic framework (MOF) structure with multiple active sites and energy transfer between the excited ligands and Ln nodes, we designed a series of Ln-MOFs and observed ECL emission at low potential, providing a novel method to realize low-potential ECL. The MOF nanoemitters were prepared using 1,3,5-tri (4-carboxyphenyl)benzene ligand and several lanthanide ions as nodes through mild hydrothermal reaction. Interestingly, strong ECL emission at +0.75 V of peak potential was observed in the ECL-potential curve of Tb-based MOF using 2,2',2″-nitrilotriethanol as coreactant, which was beneficial for reducing background interference in biosensing, and this ECL emission was attributed to the energy transfer between Tb and excited ligand. This low-potential ECL was then applied to construct an ECL biosensor with newly developed Cas12a-based method for selective detection of microRNA-155 without the help of strand displacement or reverse transcription. For this ECL system, the limit of detection was 0.78 nM, and the overall detection time was 2.5 h. The Ln-MOF nanoemitter provides a robust ECL platform to selectively detect various targets by integrating new bio-related techniques.

Tailored Cis-Trans Isomeric Metal-Covalent Organic Frameworks for Coordination Configuration-Dependent Electrochemiluminescence.

Precise manipulation of the coordination configuration within substances can modulate the band structure and catalytic properties of the target material. Metal-covalent organic frameworks (MCOFs), a crystal material amalgamating the benefits of metal-organic frameworks (MOFs) and covalent organic frameworks (COFs), can integrate a predetermined coordination environment into the frameworks for amplifying the catalytic effect. In this study, we delicately synthesize isomeric MCOFs using bis(glycinato)copper as the aminoligand via kinetically and thermodynamically favorable pathways to yield cis-MCOF and trans-MCOF products, respectively, thereby introducing a cis-trans isomeric coordination field into the framework. Moreover, the twisted skeleton derived from the flexibility of amino acid and ß-ketoenamine linkages endows trans-MCOF with surprising water dispersibility. Compared to cis-MCOF, the trans isomerism displays a significant enhancement in cathodic electrochemiluminescence via the catalysis of Cu nodes toward K2S2O8. The density of states analysis shows that the d-band center of trans-MCOF is closer to the Fermi level, leading to more stable adsorption binding to promote the catalysis. This study is the first report on constructing predesign coordination configuration MCOFs via an easy-handling method, which gives the guidelines for the design of amino acid-based MCOF materials.

Reticular Ratchets for Directing Electrochemiluminescence.

Electrochemiluminescence (ECL) involves charge transfer between electrochemical redox intermediates to produce an excited state for light emission. Ensuring precise control of charge transfer is essential for decoding ECL fundamentals, yet guidelines on how to achieve this for conventional emitters remain unexplored. Molecular ratchets offer a potential solution, as they enable the directional transfer of energy or chemicals while impeding the reverse movement. Herein, we designed 10 pairs of imine-based covalent organic frameworks as reticular ratchets to delicately manipulate the intrareticular charge transfer for directing ECL transduction from electric and chemical energies. Aligning the donor and acceptor (D-A) directions with the imine dipole effectively facilitates charge migration, whereas reversing the D-A direction impedes it. Notably, the ratchet effect of charge transfer directionality intensified with increasing D-A contrast, resulting in a remarkable 680-fold improvement in the ECL efficiency. Furthermore, dipole-controlled exciton binding energy, electron/hole decay kinetics, and femtosecond transient absorption spectra identified the electron transfer tendency from the N-end toward the C-end of reticular ratchets during ECL transduction. An exponential correlation between the ECL efficiency and the dipole difference was discovered. Our work provides a general approach to manipulate charge transfer and design next-generation electrochemical devices.

Stepwise Protonation of Three-Dimensional Covalent Organic Frameworks for Enhancing Hydrogen Peroxide Photosynthesis.

Three-dimensional covalent organic frameworks (3D COFs), recognized for their tailorable structures and accessible active sites, offer a promising platform for developing advanced photocatalysts. However, the difficulty in the synthesis and functionalization of 3D COFs hinders their further development. In this study, we present a series of 3D-bcu-COFs with 8 connected porphyrin units linked by linear linkers through imine bonds as a versatile platform for photocatalyst design. The photoresponse of 3D-bcu-COFs was initially modulated by functionalizing linear linkers with benzo-thiadiazole or benzo-selenadiazole groups. Furthermore, taking advantage of the well-exposed porphyrin and imine sites in 3D-bcu-COFs, their photocatalytic activity was optimized by stepwise protonation of imine bonds and porphyrin centers. The dual protonated COF with benzo-selenadiazole groups exhibited enhanced charge separation, leading to an increased photocatalytic H2O2 production under visible light. This enhancement demonstrates the combined benefits of linker functionalization and stepwise protonation on photocatalytic efficiency.

Metagenomics and untargeted metabolomics analyses to unravel the formation mechanism of characteristic metabolites in Cantonese soy sauce during different fermentation stages.

Cantonese soy sauce (CSS) is an important Chinese condiment due to its distinctive flavor. Microorganisms play a significant role in the flavor formation of CSS during fermentation. However, the correlation between microbes and flavor compounds as well as the potential fermentation mechanism remained poorly uncovered. Here we revealed the dynamic changes of microbial structure and characteristics metabolites as well as their correlation of CSS during the fermentation process. Metagenomics sequencing analysis showed that Tetragenococcus halophilus, Weissella confusa, Weissella paramesenteroides, Aspergillus oryzae, Lactiplantibacillus plantarum, Weissella cibaria were top six dominant species from day 0 to day 120. Sixty compounds were either positively or tentatively identified through untargeted metabolomics profile and they were 27 peptides, amino acids and derivatives, 8 carbohydrates and conjugates, 14 organic acids and derivatives, 5 amide compounds, 3 flavonoids and 3 nucleosides. Spearman correlation coefficient indicated that Tetragenococcus halophilus, Zygosaccharomyces rouxii, Pediococcus pentosaceus and Aspergillus oryzae were significantly related with the formation of taste amino acids and derivatives, peptides and functional substances. Additionally, the metabolisms of flavor amino acids including 13 main free amino acids were also profiled. These results provided valuable information for the production practice in the soy sauce industry.

Ultrastable Anion Radicals in Ligand-Dimerized Frameworks for Self-Accumulated Electrochemiluminescence.

Electrochemiluminescence (ECL) is a light-emitting process that occurs via an annihilation reaction among energetic radical intermediates, whose stabilities determine the ECL efficiency. In this study, a ligand-dimerized metal-organic framework (MOF) with ultrastable anion radical is designed as an efficient nanoemitter for self-accumulated ECL. Due to the nonplanar structure of perylene diimide (PDI) derivate, two PDI ligands in the framework form a J-dimer unit with a vertical distance of ∼5.74 Å. In cathodic scanning, the ligand-dimerized MOF demonstrates three-step ECL emissions with a gradual increase in ECL intensity. Unlike the decrease in the PDI ligand, the self-accumulated ECL of the MOF was observed with 16.8-fold enhancement due to the excellent stability of radical intermediates in frameworks. Electron paramagnetic resonance demonstrated the ultrastability of free radicals in the designed frameworks, with 82.2% remaining even after one month of storage. Density functional theory calculations supported that PDI dimerization was energetically favorable upon successive electron injection. Moreover, the ECL wavelength is 610 nm, corresponding to the emission of excited dimers. The radical-stabilized reticular nanoemitters open up a new platform for decoding the fundamentals of self-accumulated ECL systems.

Bimodal Oxidation Electrochemiluminescence Mechanism of Coreactant-Embedded Covalent Organic Frameworks via Postsynthetic Modification.

Electrochemiluminescence (ECL) efficiency is determined by charge transfer between coreactants and emitters in coreactant systems, which are usually limited by their slow intermolecular charge transfer. In this study, a covalent organic framework (COF) with aldehyde residue was synthesized, and then coreactants were covalently integrated into the skeleton through the postsynthetic modification strategy, resulting in a crystalline coreactant-embedded COF nanoemitter (C-COF). Compared to the pristine COF with an equivalent external coreactant, C-COF exhibited an extraordinary 1008-fold enhancement of ECL intensity due to the rapid intrareticular charge transfer. Significantly, with the pH increase, C-COF shows protonation-induced ECL enhancement for the first ECL peaked at +1.1 V and an opposite trend for the second ECL at +1.4 V, which were attributed to the antedating oxidation of coreactant in framework and COF self-oxidation, respectively. The resulting bimodal oxidation ECL mechanism was rationalized by spectral characterization and density functional theory calculations. The postsynthetic coreactant-embedded nanoemitters present innovative and universal avenues for advancing ECL systems.

Sub-Second Electrochemiluminescence Imaging Assay of SARS-CoV-2 Nucleocapsid Protein Based on Reticulation of Endo-Coreactants.

The nonphotodriven electrochemiluminescence (ECL) imageology necessitates concentrated coreacting additives plus longtime exposures. Seeking biosafe and streamlined ensembles can help lower the bar for quality ECL bioimaging to which call the crystallized endo-coreaction in nanoreticula might provide a potent solution. Herein, an exo-coreactant-free ECL visualizer was fabricated out in one-pot, which densified the dyad triethylamine analogue: 1,4-diazabicyclo-[2.2.2]octane (DABCO) in the lamellar hive of 9,10-di(p-carboxyphenyl)anthracene (DPA)-Zn2+. This biligated non-noble metal-organic framework (m-MOF) facilitated a self-contained anodic ECL with a yield as much as 70% of Ru(bPy)32+ in blank phosphate buffered saline. Its featured two-stage emissions rendered an efficient and endurant CCD imaging at 1.0 V under mere 0.5 s swift snapshots and 0.1 s step-pulsed stimulation. Upon structural and spectral cause analyses as well as parametric set optimization, simplistic ECL-graphic immunoassay was mounted in the in situ imager to enact an ultrasensitive measurement of coronaviral N-protein in both signal-on and off modes by the privilege of straight surface amidation on m-MOFs, resulting in a wide dynamic range (10-4-10 ng/mL), a competent detection limit down to 56 fg/mL, along with nice precision and parallelism in human saliva tests. The overall work manifests a rudimentary endeavor in self-sufficient ECL visuality for brisk, biocompatible, and brilliant production of point-of-care diagnostic "Big Data".

Photocurrent Polarity Reversal Induced by Electron-Donor Release for the Highly Sensitive Photoelectrochemical Detection of Vascular Endothelial Growth Factor 165.

Photocurrent polarity reversal is a switching process between the anodic and cathodic pathways and is critical for eliminating false positivity and improving detection sensitivity in photoelectrochemical (PEC) sensing. In this study, we construct a PEC sensor with excellent photocurrent polarity reversal induced by ascorbic acid (AA) as an electron donor with the energy level matching the photoactive material zirconium metal-organic framework (ZrMOF). The ZrMOF-modified electrode demonstrates cathodic photocurrent in the presence of O2 as an electron acceptor, while the anodic photocurrent is generated in the presence of AA, achieving photocurrent polarity reversal. By the in situ release of AA from AA-encapsulated apoferritin modified with DNA 2 (AA@APO-S2) as a detection tag in the presence of trypsin after the recognition of hairpin DNA-modified indium tin oxide to the reaction product of aptamer/DNA 1 with the target protein and the following rolling cycle amplification for introducing the detection tag to the sensing interface, the reversed photocurrent shows an enhanced photocurrent response to the target protein, leading to a highly sensitive PEC sensing strategy. This strategy realizes the detection of vascular endothelial growth factor 165 with good specificity, a wide linear range, and a low detection limit down to 5.3 fM. The actual sample analysis offers the detection results of the proposed PEC sensor comparable to those of commercial enzyme-linked immunosorbent assay tests, indicating the promising application of the photocurrent polarity reversal-based PEC sensing strategy in biomolecule detection and clinical diagnosis.

Nanoconfined Cathodic Electrochemiluminescence for Self-Sensitized Bioimaging of Membrane Protein.

Self-enhanced electrochemiluminescence (ECL) can be achieved via the confinement of coreactants and ECL emitters in a single nanostructure. This strategy has been used for the design of anodic ECL systems with amine compounds as coreactants. In this work, a novel confinement system was proposed by codoping positively charged ECL emitter tris(2,2'-bipyridine)ruthenium(II) (Ru(bpy)32+) and negatively charged coreactant peroxydisulfate (S2O82-) in silica nanoparticles. The codoping process could be performed by introducing S2O82- in cationic poly(diallyldimethylammonium chloride) (PDDA) to form PDDA@S2O82- and then encapsulating it and Ru(bpy)32+ in the Triton X-100 vesicle followed by the hydrolysis of tetraethyl ortosilicate, surface modification, and demulsification. The obtained RuSSNs exhibited good homogeneity, excellent monodispersity, acceptable biocompatibility, and 2.9-fold stronger ECL emission than Ru(bpy)32+-doped silica nanoparticles at an equal amount of nanoparticles in the presence of 0.1 M K2S2O8. Thus, an in situ self-sensitized cathodic ECL imaging method was designed for the monitoring of glycoprotein on living cell membranes. This work provides a new way for the modification, enhancement, and application of nano-ECL emitters in biological analysis.

Gold Microbeads Enabled Proximity Electrochemiluminescence for Highly Sensitive and Size-Encoded Multiplex Immunoassays.

Developing highly sensitive multiplex immunoassays is urgently needed to guide medical research and improve clinical diagnosis. Here, we report the proximity electrochemiluminescence (ECL) generation enabled by gold microbeads (GMBs) for improving the detection sensitivity and multiplexing capacity of ECL immunoassays (ECLIAs). As demonstrated by microscopy and finite element simulation, GMBs can function as spherical ultramicroelectrodes for triggering ECL reactions in solutions. Employing GMBs as solid carriers in the bead-based ECLIA, the electrochemical oxidation of a coreactant can occur at both the GMB surface and the substrate electrode, allowing the coreactant radicals to diffuse only a short distance of ∼100 nm to react with ECL luminophores that are labeled on the GMB surface. The ECL generation via this proximity low oxidation potential (LOP) route results in a 21.7-fold increase in the turnover frequency of ECL generation compared with the non-conductive microbeads that rely exclusively on the conventional LOP route. Moreover, the proximity ECL generation is not restricted by the diffusion distance of short-lived coreactant radicals, which enables the simultaneous determination of multiple acute myocardial infarction biomarkers using size-encoded GMB-based multiplex ECLIAs. This work brings new insight into the understanding of ECL mechanisms and may advance the practical use of multiplex ECLIAs.

Reticular Electrochemiluminescence Nanoemitters: Structural Design and Enhancement Mechanism.

ConspectusElectrochemiluminescence (ECL) is a powerful transduction technique, which depends critically on the formation of the excited emitter through the charge transfer between the electrochemical reaction intermediates of the emitter and the co-reactant/emitter. The exploration of ECL mechanisms for conventional nanoemitters is limited due to the uncontrollable charge transfer process. With the development of molecular nanocrystals, reticular structures such as metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) have been utilized as atomically precise semiconducting materials. The long-range order in crystalline frameworks and the tunable coupling among building blocks promote the quick development of electrically conductive frameworks. Especially, the reticular charge transfer can be regulated by both interlayer electron coupling and intralayer topology-templated conjugation. By modulating intramolecular or intermolecular charge mobility, reticular structures could serve as promising candidates for enhancing ECL. Thus, reticular crystalline nanoemitters with different topologies provide a confined platform to understand ECL fundamentals for designing next-generation ECL devices.Aiming at exploring the mechanism of ECL emission, our group has developed a series of ECL nanoemitters as well as enhancement strategies of ECL emission in the past 20 years. A series of water-soluble ligand-capped quantum dots were introduced as ECL nanoemitters to create sensitive analytical methods for detecting and tracing biomarkers. The functionalized polymer dots were also designed as ECL nanoemitters for imaging of membrane proteins with signal transduction strategies of dual resonance energy transfer and dual intramolecular electron transfer. To decode the ECL fundamental and enhancement mechanisms, an electroactive MOF with accurate molecular structure was first constructed with two redox ligands as a highly crystallized ECL nanoemitter in aqueous medium. Through the mixed-ligand approach, luminophores and co-reactants were integrated into one MOF structure for self-enhanced ECL. Furthermore, several donor-acceptor COFs were developed as efficient ECL nanoemitters with tunable intrareticular charge transfer. The atomically precise structure of conductive frameworks established clear correlations between the structure and charge transport in these materials. Therefore, reticular materials as crystalline ECL nanoemitters have demonstrated both proof of concept and mechanistic innovation.In this Account, taking advantage of reticular materials with accurate molecular structure, we survey the design of the electroactive reticular materials including MOFs and COFs as crystalline ECL nanoemitters at the molecular level. The enhancement mechanisms of ECL emission of various topology frameworks are discussed via the regulation of reticular energy transfer and charge transfer and the accumulation of anion/cation radicals. Our perspective on the reticular ECL nanoemitters is also discussed. This Account provides a new avenue for designing molecular crystalline ECL nanoemitters and decoding the fundamentals of ECL detection methods.

A Versatile G-Quadruplex (G4)-Coated Upconverted Metal-Organic Framework for Hypoxic Tumor Therapy.

Given the complexity of the tumor microenvironment, multiple strategies are being explored to tackle hypoxic tumors. The most efficient strategies combine several therapeutic modalities and typically requires the development of multifunctional nanocomposites through sophisticated synthetic procedures. Herein, the G-quadruplex (G4)-forming sequence AS1411-A (d[(G2 T)4 TG(TG2 )4 A]) is used for both its anti-tumor and biocatalytic properties when combined with hemin, increasing the production of O2 ca. two-fold as compared to the parent AS1411 sequence. The AS1411-A/hemin complex (GH) is grafted on the surface and pores of a core-shell upconverted metal-organic framework (UMOF) to generate a UMGH nanoplatform. Compared with UMOF, UMGH exhibits enhanced colloidal stability, increased tumor cell targeting and improved O2 production (8.5-fold) in situ. When irradiated by near-infrared (NIR) light, the UMGH antitumor properties are bolstered by photodynamic therapy (PDT), thanks to its ability to convert O2 into singlet oxygen (1 O2 ). Combined with the antiproliferative activity of AS1411-A, this novel approach lays the foundation for a new type of G4-based nanomedicine.

Postsynthetic Annulation of Three-Dimensional Covalent Organic Frameworks for Boosting CO2 Photoreduction.

Three-dimensional covalent organic frameworks (3D COFs), with interconnected pores and exposed functional groups, provide new opportunities for the design of advanced functional materials through postsynthetic modification. Herein, we demonstrate the successful postsynthetic annulation of 3D COFs to construct efficient CO2 reduction photocatalysts. Two 3D COFs, NJU-318 and NJU-319Fe, were initially constructed by connecting hexaphenyl-triphenylene units with pyrene- or Fe-porphyrin-based linkers. Subsequently, the hexaphenyl-triphenylene moieties within the COFs were postsynthetically transformed into π-conjugated hexabenzo-trinaphthylene (pNJU-318 and pNJU-319Fe) to enhance visible light absorption and CO2 photoreduction activity. The optimized photocatalyst, pNJU-319Fe, shows a CO yield of 688 µmol g-1, representing a 2.5-fold increase compared to that of unmodified NJU-319Fe. Notably, the direct synthesis of hexabenzo-trinaphthylene-based COF catalysts was unsuccessful due to the low solubility of conjugated linkers. This study not only provides an effective method to construct photocatalysts but also highlights the unlimited tunability of 3D COFs through structural design and postsynthetic modification.

A Self-Templated Design Approach toward Multivariate Metal-Organic Frameworks for Enhanced Oxygen Evolution.

Multivariate metal-organic framework (MOF) is an ideal electrocatalytic material due to the synergistic effect of multiple metal active sites. In this study, a series of ternary M-NiMOF (M = Co, Cu) through a simple self-templated strategy that the Co/Cu MOF isomorphically grows in situ on the surface of NiMOF is designed. Owing to the electron rearrange of adjacent metals, the ternary CoCu-NiMOFs demonstrate the improved intrinsic electrocatalytic activity. At optimized conditions, the ternary Co3 Cu-Ni2 MOFs nanosheets give the excellent oxygen evolution reaction (OER) performance of current density of 10 mA cm-2 at low overpotential of 288 mV with a Tafel slope of 87 mV dec-1 , which is superior to that of bimetallic nanosheet and ternary microflowers. The low free energy change of potential-determining step identifies that the OER process is favorable at Cu-Co concerted sites along with strong synergistic effect of Ni nodes. Partially oxidized metal sites also reduce the electron density, thus accelerating the OER catalytic rate. The self-templated strategy provides a universal tool to design multivariate MOF electrocatalysts for highly efficient energy transduction.