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The use of mixed microalgae offers an effective solution for the management of contamination risks in cultivation while enhancing economic viability. In this study, mixed microalgae were used for the first time for the removal of copper (Cu) and nickel (Ni) from aqueous solutions. The characteristics of the adsorbents were examined thoroughly, and the adsorption process was assessed using isotherms, kinetics, and thermodynamics. Particle size, concentration, contact time, temperature, and pH were among the variables assessed. The findings demonstrated that, at an initial concentration of 100 mg L–1 and a pH of 6, the maximum adsorption of Cu with a particle size of 1 mm (90.20%) took place in 60 min. The highest adsorption rate (78.25%) was found for Ni. Microalgae performed best over 180 min at room temperature and at pH values that promoted metal dissolution. The removal percentages of wet and dried microalgae were comparable, and the wet adsorbent was more economical. It was feasible to remove both metals at the same time. Up to three cycles of adsorbent reuse were possible, with sodium hydroxide treatment offering superior removal to hydrochloric acid. Thermodynamic analysis demonstrated that this process, which results in a disordered state, is exothermic and spontaneous. [ABSTRACT FROM AUTHOR]

Oxidative stress caused by pregnancy‐induced hypertension syndrome significantly affects the health of pregnant women. Hydrogen sulfide is a typical gaseous signal molecule against oxidative stress, and it is of profound significance to develop a detection method. In this study, a stimuli‐responsive hydrogel was constructed based on the coordination and bonding principle of metal ions and chitosan (CS) to realize the quantitative detection of hydrogen sulfide (H2S). The chain of CS contains a large number of amino groups and hydroxyl groups, which can form the coordination structure with Cu2+, triggering CS to form a stable hydrogel. The hydrogel can be formed within about 5 s, which has the characteristics of rapid preparation. In the presence of target H2S, the cross‐linking agent Cu2+ in the hydrogel can compete out, resulting in the collapse of the hydrogel and the release of the electrochemical probe. By detecting the concentration of the released electrochemical probe, the quantitative detection of H2S can be achieved. The prepared hydrogel has a good linear relationship with the concentration of H2S from 1 μM to 60 μm. At the same time, the hydrogel has good specificity and stability, and it can be applied to the detection of H2S in serum samples. [ABSTRACT FROM AUTHOR]

In this work, two novel pyrimidine‐cored covalent organic frameworks TpTap‐COF and TpTan‐COF were synthesized for the first time and used for the adsorption of heavy metal ions in aqueous solution. Both COFs are nanofiber clusters with preferable crystallinity and thermal stability. The impact parameters such as pH value, shaking time, initial concentration, and temperature were studied by batch adsorption experiments in the multi‐metal ions system. The adsorption of six metal ions onto COFs follows the pseudo‐second‐order kinetic model and the Freundlich isotherm model, which is a chemical adsorption process that occurs on non‐uniform surfaces. The adsorption rate is determined by both film diffusion and intraparticle diffusion. Further research on the adsorption of copper ions onto COFs indicates the formation of metal complexes between O#N#N/O#O chelating sites in the COF skeleton and Cu ions through the sharing of lone pair electrons. [ABSTRACT FROM AUTHOR]

The combination of cuproptosis and immune checkpoint inhibition has shown promise in treating malignant tumors. However, it remains a challenge to deliver copper ions and immune checkpoint inhibitors efficiently and simultaneously to tumors. Herein, a mitochondria‐targeted nanoscale coordination polymer particle, Cu/TI, comprising Cu(II), and a triphenylphosphonium conjugate of 5‐carboxy‐8‐hydroxyquinoline (TI), for effective cuproptosis induction and programmed cell death‐1 (PD‐L1) downregulation is reported. Upon systemic administration, Cu/TI efficiently accumulates in tumor tissues to induce immunogenic cancer cell death and reduce PD‐L1 expression. Consequently, Cu/TI promotes the intratumoral infiltration and activation of cytotoxic T lymphocytes to greatly inhibit tumor progression of colorectal carcinoma and triple‐negative breast cancer in mouse models without causing obvious side effects. [ABSTRACT FROM AUTHOR]

ABSTRACT This study highlights the synergistic interplay between a Lewis acidic copper ion and a dissociated ligand from Cu(triNHC) complexes in the synthesis of cyclic carbonates from CO2 and epoxy compounds. The reactions were found to proceed efficiently under Cu(triNHC)‐catalyzed conditions, yielding significant quantities of cyclic carbonates across various epoxy substrates encompassing amine, sulfide, and ether functionalities. Stereochemical analyses underscore a pronounced propensity for retaining the stereochemistry of epoxy compounds in the resultant carbonates. This suggests a mechanism involving double inversion of stereochemistry during the reaction, which comprises catalyst‐mediated epoxide ring opening, subsequent CO2 addition, and carbonate ring closing. These findings align with established mechanisms for CO2 fixation reactions, shedding light on the intricate pathways underlying this catalytic process. [ABSTRACT FROM AUTHOR]

Lead halide perovskites have been explored ardently in the past decade owing to their excellent photophysical properties. High‐temperature cation exchange reactions have been employed to improve the stability and performance in perovskite lattice, but lacks control over size, shape, and stoichiometry. Herein, the solution phase interaction of cesium lead bromide (CsPbBr3) nanocrystals with monovalent and bivalent copper ions, under ambient conditions is systematically investigated. The introduction of Cu1+ explicitly initiates a one‐dimensional growth with a distinct phase transition, that is from cubic to orthorhombic, while Cu2+ induces a partial exchange with Pb2+ with no phase change. DFT calculations suggest that Cu1+ induces structural distortion via Cs1+ substitution, altering the Goldschmidt tolerance factor and perovskite octahedral tilting, leading to the phase transition. Additionally, the oleic acid/amine ligands used to stabilize the nanocrystals, are preferentially etched away to form complexes with Cu1+, initializing an oriented growth of the nanocubes to nanorods. A mechanistic investigation of the evolution of the nanorods gave insights on tuning the tolerance factor via room temperature modifications and cation exchanges in perovskites for anisotropy and morphology tuning. This effortlessly obtained perovskite nanorods with Cu1+ could find effective applications in optoelectronics, and as novel photocatalysts. [ABSTRACT FROM AUTHOR]

Doping of brushite cements with metal ions can entail many positive effects on biological and physicochemical properties. Cu2+ ions are known to exhibit antibacterial properties and can additionally have different positive effects on cells as trace elements, whereas high Cu2+ concentrations are cytotoxic. For therapeutical applications of bone cement, a combination of good biocompatibility and sufficient mechanical properties is required. Therefore, the aim of this study was to investigate different physicochemical and biological aspects, relevant for application, of a brushite cement with Cu2+‐doped β‐tricalcium phosphate, monocalcium phosphate monohydrate and phytic acid as setting retarder. Additionally, the ion release was compared with a cement with citric acid as setting retarder. The investigated cements showed good injectability coefficients, as well as compressive strength values sufficient for application. Furthermore, no antibacterial effects were detected irrespective of the Cu2+ concentration or the bacterial strain. The cell experiments with eluate samples showed that the viability of MC3T3‐E1 cells tended to decrease with increasing Cu2+ concentration in the cement. It is suggested that these biological responses are caused by the difference in the Cu2+ release from the hardened cement depending on the solvent medium. Furthermore, the cements showed a steady release of Cu2+ ions to a lesser extent in comparison with a cement with citric acid as setting retarder, where a burst release of Cu2+ was observed. In conclusion, despite the anticipated antibacterial effect of Cu2+‐doped cements was lacking and mammalian cell viability was slightly affected, Cu2+‐concentrations maintained the physicochemical properties as well as the compressive strength of cements and the slow ion release from cements produced with phytic acid is considered advantageous compared to citric acid‐based formulations. [ABSTRACT FROM AUTHOR]

Nanomedicines loaded in macrophages (MAs) can actively target tumors without dominantly relying on the enhanced permeability and retention (EPR) effect, making them effective for treating EPR‐deficient malignancies. Herein, copper‐crosslinked carbon dot clusters (CDCs) are synthesized with both photodynamic and chemodynamic functions to manipulate MAs, aiming to direct the MA‐mediated tumor targeting. First, green fluorescent CDs (g‐CDs) are prepared by a one‐step hydrothermal method. Subsequently, the g‐CDs are complexed with divalent copper ions to form copper‐crosslinked CDCs (g‐CDCs/Cu), which are incubated with MAs for their manipulation. Experimental results revealed that the prepared g‐CDCs/Cu displayed good aqueous dispersibility and fluorescent emission properties. The nanoassemblies can be activated to deplete the overexpressed glutathione (GSH) and generate reactive oxygen species (ROS) in the presence of laser irradiation through the combined Cu‐mediated chemodynamic therapy and CD‐mediated photodynamic therapy. Furthermore, the ROS produced in MAs enabled polarization of MAs to antitumor M1 phenotype, suggesting the future potential use to reverse the immunosuppressive tumor microenvironment. These results obtained from the current study suggest a significant potential to develop g‐CDCs/Cu for GSH depletion, ROS generation, and MA M1 polarization as a theransotic agent to tackle cancer. [ABSTRACT FROM AUTHOR]

Radix Paeoniae Alba is an important plant resource and valuable tonic in traditional Chinese medicine. The radix of Radix Paeoniae Alba is rich in starch. There are few reports of Radix Paeoniae Alba starch. In present study, the Radix Paeoniae Alba starch is extracted, citrate esterified starches are prepared, the starch‐based hydrogels are synthesized, and adsorptive properties are investigated. The investigation suggests that Radix Paeoniae Alba starch‐based adsorbent is promising as an efficient and sustainable adsorbent for copper ions and methylene blue removal; therefore, Radix Paeoniae Alba starch has an appealing application prospect in adsorption for scavenging metal ions and dyes from real complex waste liquid. [ABSTRACT FROM AUTHOR]

Organic upconverters made by integrating an infrared‐sensitive photodetector with a light‐emitting diode offer a low‐cost route to visualize images taken in the infrared. However, making such devices sufficiently efficient is challenging. Here, upconversion devices are demonstrated with an efficiency of 13.9% for converting infrared photons (980 nm, 5 mW cm−2) to visible photons (575 nm). Infrared photons are detected with a photomultiplication photodetector that includes a copper thiocyanate electron‐blocking/injection layer and an infrared‐sensitive squaraine dye dispersed (3 wt−%) in a fullerene matrix. At turn‐on, the detector achieves an external quantum efficiency of 1200% (at 1020 nm, −10 V, 44 µW cm−2). Photomultiplication occurs via hole trap‐induced injection of electrons. In the upconverter, these electrons are driven into the emitter and recombine with holes under visible light emission. During operation the photodetector current increases because, presumably, rearranging mobile ions in copper thiocyanate narrows the injection barrier. Thereby, the upconverter photoconversion efficiency gradually increases to 18.7%. The performance of the present upconverter is limited by the not‐yet‐ideal charge‐blocking/injection layer, which is too thick and blocks electrons in the dark insufficiently. With thin and compact charge‐blocking layers at hand, the device concept paves the way for widespread use in sensitive infrared imaging. [ABSTRACT FROM AUTHOR]

Pesticides in environmental samples pose significant risks to ecosystems and human health since they require precise and efficient detection methods. Imidacloprid (IMI), a widely used neonicotinoid insecticide, exemplifies these hazards due to its potential toxicity. This study addresses the urgent need for improved monitoring of such contaminants by introducing a novel fluorometric method for detecting IMI using nitrogen‐doped graphite carbon dots (N‐GCDs). The sensor operates by quenching fluorescence through the interaction of Cu2+ ions with N‐GCDs. Subsequently, IMI binds to the imidazole group, chelates with Cu2+, and restores the fluorescence of N‐GCDs. This alternating fluorescence behavior allows for the accurate identification of both Cu2+ and IMI. The sensor exhibits linear detection ranges of 20–100 nM for Cu2+ and 10–140 μg/L for IMI, with detection limits of 18 nM and 1.2 μg/L, respectively. The high sensitivity of this sensor enables the detection of real‐world samples, which underscores its potential for practical use in environmental monitoring and agricultural safety. [ABSTRACT FROM AUTHOR]

Liquid‐solid triboelectric nanogenerator (LS‐TENG) harvests energy efficiently while eliminating wear issues associated with solid‐solid TENG. However, the effect of ions or charges in the liquid on output performance needs further examination. In this work, the impact of fluorine and copper ions introduced through deionized water with sodium fluoride (DI‐NaF) and deionized water with copper sulfate (DI‐CuSO4) solution on the output voltage, charge and current of a tubular LS‐TENG with polytetrafluoroethylene (PTFE) and Nylon as solid materials is examined. The results indicate that fluorine and copper ions have opposite effects on PTFE and Nylon LS‐TENG's output. The fluorine (F−) ions enhance the triboelectric effect and charge transfer in Nylon LS‐TENG, increasing output, while they hinder the charge transfer process in PTFE LS‐TENG, consequently decreasing its output. Conversely, the copper (Cu2+) ions have a positive effect on the output of PTFE LS‐TENG and a detrimental effect on Nylon LS‐TENG's output. Moreover, the results indicate that LS TENG's output performance depends on the charges of solid and liquid triboelectric materials. Thus, this study provides insights into material‐ion interaction in LS‐TENG and underscores the importance of triboelectric material selection for optimizing output performance. [ABSTRACT FROM AUTHOR]

Dopamine (DA), a critical catecholamine in mammals, functions as a significant biological indicator for specific diseases. The precise and timely identification of DA is essential for disease monitoring and prevention. In this study, copper nanoclusters (Cu NCs) were synthesized using polyvinyl pyrrolidone (PVP) as the protective ligand and L‐ascorbic acid (L‐AA) as the reducing agent via a simple hydrothermal process. The produced PVP−Cu NCs displayed strong blue emission at 427 nm when excited at 365 nm. In alkaline conditions, DA was able to selectively inhibit the fluorescence of PVP−Cu NCs. The investigation of the mechanism revealed that dopamine self‐polymerization resulted in the formation of polydopamine, which inhibited the emission of PVP−Cu NCs at 427 nm due to the inner filter effect (IFE). Based on the above phenomenon, a simple and selective analytical method for DA determination was developed. The fluorescence intensity of PVP−Cu NCs demonstrated a reliable response to DA concentrations within the range of 5 to 200 μM, with a detection limit (LOD) of 1.32 μM. The proposed method was successfully utilized for the precise detection of DA in human urine samples, indicating its potential application in biomedical dopamine detection. [ABSTRACT FROM AUTHOR]

During the photochemical CO2 reduction reaction, CO2 adsorption on the catalyst's surface is a crucial step where the binding mode of the [metal‐CO2] adduct directs the product selectivity and efficiency. Herein, an ionic TiO2 nanostructure stabilized by polyoxometalates (POM), ([POM]x@TiO2), is prepared and the sodium counter ions present on the surface to balance the POMs' charge are replaced with copper(II) ions, (Cux[POM]@TiO2). The microscopic and spectroscopic studies affirm the copper exchange without altering the TiO2 core and weak coordination of copper (II) ions to the POMs' surface. Band structure analysis suggests the photo‐harvesting efficiency of the TiO2 core with the conduction band edge higher than the reduction potential of CuII/I and multi‐electron CO2 reduction potentials. Photochemical CO2 reduction with Cux[POM]@TiO2 results in 30 μmol gcat.−1 CO (79 %) and 8 μmol gcat−1 of CH4 (21 %). Quasi‐in‐situ Raman study provides evidence in support of CO2 adsorption on the Cux[POM]@TiO2 surface. 13C and D2O labeling studies affirm the {Cu‐[CO2]−} adduct formation. Despite the photo‐harvesting ability of Nax[POM]@TiO2 itself, the poor CO2 adsorption ability of sodium ions highlights the crucial role of copper ion CO2 photo‐reduction. Characterization of the {M‐[η2‐CO2]−} species via surface tuning validates the CO2 activation and photochemical reduction pathway proposed earlier. [ABSTRACT FROM AUTHOR]

Here, we report the reactivity of copper(I) clusters toward sulfide ions; these sulfide copper(I) clusters have attracted much attention due to their relevance to biologically active centers and their fascinating structural and photophysical properties. Treatment of the CuI3RhIII2 pentanuclear complex, [Cu3{Rh(aet)3}2]3+ (aet=2‐aminoethanethiolate), in which a {CuI3}3+ cluster moiety is bound by two fac‐[Rh(aet)3] metalloligands, with NaSH in water produced the CuI6RhIII4 decanuclear complex, [Cu6S{Rh(aet)3}4]4+, accompanied by the dimerization of [Cu3{Rh(aet)3}2]3+ and the incorporation of a sulfide ion at the center. While similar treatment using the analogous CuI3IrIII2 complex with fac‐[Ir(aet)3] metalloligands, [Cu3{Ir(aet)3}2]3+, produced the isostructural CuI6IrIII4 decanuclear complex, [Cu6S{Ir(aet)3}4]4+, the use of the CuI3RhIII2 complex with fac‐[Rh(apt)3] metalloligands, [Cu3{Rh(apt)3}2]3+ (apt=3‐aminopropanethiolate), resulted in the removal of one of the three CuI atoms from {CuI3}3+ to afford the CuI2RhIII2 tetranuclear complex, [Cu2{Rh(apt)3}2]2+. [ABSTRACT FROM AUTHOR]

The antimicrobial properties of copper ions can reduce the overgrowth of microorganisms to a certain extent. That reduces the amount of antibiotics used, to avoid superbugs and potential harm. The authors reviewed the antimicrobial mechanisms of copper and copper‐containing nanoparticles (NPs), focusing on the factors influencing their antimicrobial properties. They concluded that the antimicrobial properties were better in environments conducive to the precipitation of copper ions and exposure to microorganisms. Comparing copper with other metal ions leads to the question of why copper is such an important antimicrobial metal ion. In recent years, with the development of science and technology and the understanding of the microscopic world, scientists have skillfully applied the antimicrobial properties of copper in various settings, from direct contact with food to breeding and hygienic environments, and have confirmed the safety of the application. However, because of the toxic effect of NPs, the future goal is to synthesize a copper‐containing NP with good biocompatibility and antibacterial efficiency to benefit human society. [ABSTRACT FROM AUTHOR]

Copper ions in wastewater present substantial environmental hazards, toxic to aquatic species and prone to bioaccumulation. Addressing this, we present a novel cross‐linked polythiourethane (C‐PTU) as a promising chelating adsorbent for the effective removal of copper ions from wastewater. A new monomer, 5‐(2,2,2‐trifluoroacetamide) benzene‐1,3‐bis(carbonyl) isothiocyanate (TFA‐ITC), was synthesized and further condensed with a 1,4‐butane diol to produce a trifluoroacetamide functionalized polythiourethane (TFA‐PTU) and subsequently generating amine functionalized polythiourethane (A‐PTU). The cross‐linking reaction was carried out through amino groups present on the polymer backbone with terephthaloyl chloride, resulting in the formation of C‐PTU. The monomer and polymers underwent characterization using Fourier transform infrared, 1H, and 13C nuclear magnetic resonance spectroscopy, with X‐ray diffraction analyzing the resin's chain alignment. Thermogravimetric and differential scanning calorimetry assessed C‐PTU's thermal properties. The adsorption process for Cu(II) ions was studied using atomic absorption spectroscopy, optimizing conditions for maximal uptake. Results revealed that C‐PTU exhibited a significant adsorption capacity for Cu(II) ions, reaching 67% after a 2 h contact time, with optimal adsorption occurring at pH 6. The Langmuir adsorption isotherm described the sorption mechanism, indicating favorable monolayer cation adsorption via coordination with donor sites on C‐PTU. This research presents a viable solution for copper ion contamination in wastewater, illustrating C‐PTU as an efficient, environmentally friendly adsorbent, marking progress toward cleaner water resources. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs), as high‐potential electrode materials for applications in supercapacitors, have received significant attention recently. Unfortunately, MOF materials still suffer from unsatisfactory specific capacitances due to poor conductivity and limited redox active sites. Herein, a novel cobalt–copper‐based bimetal–organic framework (CoCu‐MOF) is synthesized by a bottom‐up synthesis strategy, the material properties systematically characterized, and finally investigated as a supercapacitor electrode material. The synthesized CoCu‐MOF presents a high specific surface area of 62.4 m2 g−1, and 83% of the copper ions attains the +1 oxidation state contributing to the formation of additional redox active sites and leading to the formation of dual‐redox sites. The CoCu‐MOF displays an excellent specific capacitance of 618 F g−1 at a current density of 1 A g−1, which is more than twice that of Co‐MOF and four times that of Cu‐MOF. The CoCu‐MOF retains 75% of its original capacitance after 3000 charge–discharge cycles at the current density of 1 A g−1. Overall, this work demonstrates how the bimetallic synergistic strategy can effectively enhance the electrochemical properties of MOFs by providing a higher specific surface area and by the introduction of dual redox sites. [ABSTRACT FROM AUTHOR]

Prostate, bladder, and kidney cancers are the most common malignancies of the urinary system. Chemotherapeutic drugs are generally used as adjuvant treatment in the middle, late, or recurrence stages after surgery for urologic cancers. However, traditional chemotherapy is plagued by problems such as poor efficacy, severe side effects, and complications. Copper‐containing nanomedicines are promising novel cancer treatment modalities that can potentially overcome these disadvantages. Copper homeostasis and cuproptosis play crucial roles in the development, adaptability, and therapeutic sensitivity of urological malignancies. Cuproptosis refers to the direct binding of copper ions to lipoylated components of the tricarboxylic acid cycle, leading to protein oligomerization, loss of iron–sulfur proteins, proteotoxic stress, and cell death. This review focuses on copper homeostasis and cuproptosis as well as recent findings on copper and cuproptosis in urological malignancies. Furthermore, we highlight the potential therapeutic applications of copper‐ and cuproptosis‐targeted therapies to better understand cuproptosis‐based drugs for the treatment of urological tumors in the future. [ABSTRACT FROM AUTHOR]

In this study, we present the novel combination of AE‐TPEA with RuMOF to construct an electrochemiluminescence (ECL) sensor using a TPEA‐RuMOF composite material specifically for copper ions (Cu2+) detection. Using K2S2O8 as a co‐reactant, we explored the ECL behavior of the TPEA‐RuMOF modified electrode, enabling the quantitative detection of Cu2+. Remarkably, this sensor exhibited a wide linear range from 1×10−5 to 1×10−9 M (R2=0.998) and boasted a detection limit as low as 0.41 nM, which is considerably below the EPA (Environmental Protection Agency) permissible copper ion concentration in drinking water of <1.3 mg/L. our synthesized probe offers enhanced stability and selectivity in copper ion detection. This indicates its considerable potential for high‐performance copper ion detectors. We further validated the analytical applicability of this sensor using river water samples. [ABSTRACT FROM AUTHOR]

The immunological implications of cuproptosis, a form of cell death highly sensitive to oxygen presence, remain largely unexplored in the context of tumor immunotherapy. Herein, we initially investigate the positive correlation between cuproptosis and tumor immunotherapy through bioinformatics analysis. Subsequently, an oxygen generator loaded with copper ions (Cu/APH‐M) has been constructed, which serves as an effective carrier of copper ions and crucially enhances the oxygenation of the tumor microenvironment. Importantly, Cu/APH‐M‐mediated dual strengthening of cuproptosis and radiotherapy could not only trigger a powerful antitumor immunity related to immunogenic cell death by RNA‐sequencing analysis, but also effectively inhibit the growth of both distal and in situ low rectal tumors after combined immunotherapy, creating a robust immune memory effect. Our work reveals the beneficial effects of enhanced cuproptosis in radio‐immunotherapy and elucidates its underlying mechanisms, which provides a novel approach for the synergistic integration of cuproptosis with immunotherapy and radiotherapy, broadening the scope of cuproptosis‐mediated tumor therapy. [ABSTRACT FROM AUTHOR]

The induction of cuproptosis, a recently identified form of copper‐dependent immunogenic cell death, is a promising approach for antitumor therapy. However, sufficient accumulation of intracellular copper ions (Cu2+) in tumor cells is essential for inducing cuproptosis. Herein, an intelligent cuproptosis‐inducing nanosystem is constructed by encapsulating copper oxide (CuO) nanoparticles with the copper ionophore elesclomol (ES). After uptake by tumor cells, ES@CuO is degraded to release Cu2+ and ES to synergistically trigger cuproptosis, thereby significantly inhibiting the tumor growth of murine B16 melanoma cells. Moreover, ES@CuO further promoted cuproptosis‐mediated immune responses and reprogrammed the immunosuppressive tumor microenvironment by increasing the number of tumor‐infiltrating lymphocytes and secreted inflammatory cytokines. Additionally, combining ES@CuO with programmed cell death‐1 (PD‐1) immunotherapy substantially increased the antitumor efficacy in murine melanoma. Overall, the findings of this study can lead to the use of a novel strategy for cuproptosis‐mediated antitumor therapy, which may enhance the efficacy of immune checkpoint inhibitor therapy. [ABSTRACT FROM AUTHOR]

Silicone rubber (SR) has excellent properties, such as high and low temperature resistance and weather resistance. However, the flame retardancy of SR is rather poor, which severely limits the range of application of SR. Therefore, it is necessary to make certain modifications in order to improve its flame retardancy. In this study, wollastonite, low‐melting glass powder, and phytate‐modified carbon nanotubes (CPCC) were added to SR to prepare ceramizable silicone rubber (CSR) composites with good fire safety performance. The effect of CPCC on the flame retardancy and ceramization properties of CSR materials was investigated. The results showed that, with the addition of 3 phr of CPCC, the limiting oxygen index of the CSR composite material reached 33.8%, which was 26.1% higher than that of pure SR, and its UL‐94 grade reached V‐0 grade. The results of the cone calorimeter test showed that the total heat release of the CSR composite with three parts CPCC was reduced by 26.6%, and the peak heat release rate reduced by 13.1%. In addition, after the CSR6 composite was calcined at 1000°C for 1 h, the ceramic body formed by the composite had good supporting properties, and its bending strength was as high as 6.17 MPa. [ABSTRACT FROM AUTHOR]

Human cystatin C (hCC), a small secretory protein, has gained attention beyond its classical role as a cysteine protease inhibitor owing to its potential involvement in neurodegenerative disorders. This study investigates the interaction between copper(II) ions [Cu(II)] and hCC, specifically targeting histidine residues known to participate in metal binding. Through various analytical techniques, including mutagenesis, circular dichroism, fluorescence assays, gel filtration chromatography, and electron microscopy, we evaluated the impact of Cu(II) ions on the structure and oligomerization of hCC. The results show that Cu(II) does not influence the secondary and tertiary structure of the studied hCC variants but affects their stability. To explore the Cu(II)‐binding site, nuclear magnetic resonance (NMR) and X‐ray studies were conducted. NMR experiments revealed notable changes in signal intensities and linewidths within the region 86His‐Asp‐Gln‐Pro‐His90, suggesting its involvement in Cu(II) coordination. Both histidine residues from this fragment were found to serve as a primary anchor of Cu(II) in solution, depending on the structural context and the presence of other Cu(II)‐binding agents. The presence of Cu(II) led to significant destabilization and altered thermal stability of the wild‐type and H90A variant, confirming differentiation between His residues in Cu(II) binding. In conclusion, this study provides valuable insights into the interaction between Cu(II) and hCC, elucidating the impact of copper ions on protein stability and identifying potential Cu(II)‐binding residues. Understanding these interactions enhances our knowledge of the role of copper in neurodegenerative disorders and may facilitate the development of therapeutic strategies targeting copper‐mediated processes in protein aggregation and associated pathologies. [ABSTRACT FROM AUTHOR]

Heavy metal in excess quantity is one of the major inorganic pollutants in water. It causes several hazards to human life and ecosystem. It exists in traces in most of the commonly available drinking water sources from lakes, ponds, wells, etc., However, their presence in treated water is relatively significant. As the treated water is primarily used for agricultural purposes, it is necessary to monitor and measure their concentration. This requires sensing of metals in aqueous medium with good sensitivity and stability. Recently, nanosensors coupled with electrochemical transducer is preferred for analyzing heavy metal in aqueous solutions. In this work, Silver oxide‐bismuth oxy bromide coated with nafion is proposed as an electrochemical sensor for detection of heavy metal ions in aqueous solution. Cyclic voltammetry (CV) behavior of the proposed electrode is observed in different electrolytes. Further, Differential Pulse Voltammetry (DPV) study shows that current increases with trace nickel and copper metal ions of different concentration. Further, machine learning (ML) algorithms such as Naïve Bayes, ANN, SVM and decision trees are employed for nickel ions to train the cyclic voltammetry data and evaluate its performance. Naïve Bayes algorithm provides the best accuracy of 93.2% among all the models. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER) is an integral step in the water‐splitting process. Hence, to promote OER, efficient catalysts are required to lower the energy barriers at the electrode/electrolyte interface. Low‐cost and highly active catalysts are in great demand. Herein, a ternary metal oxide, CoCuMnOx, synthesized by a facile hydrothermal method is reported, which possesses excellent catalytic ability for OER in alkaline electrolytes. The nanoscale morphology of the catalyst with flower‐like nanostructures is instrumental in increasing the electrochemical surface area of the electrode. The presence of multivalent ions and the incorporation of copper greatly enhance the electrochemical properties of the catalysts. The catalysts typically demonstrate an overpotential value of 220 mV for achieving 10 mA cm−2 current density and a Tafel slope of 73 mV dec−1. The catalysts demonstrate good stability with minimal degradation in OER activity even after 20 h of chronopotentiometry test. For practical applications, this low‐cost material holds great potential. [ABSTRACT FROM AUTHOR]

Selective photoreduction of CO2 to multicarbon products, is an important but challenging task, due to high CO2 activation barriers and insufficient catalytic sites for C−C coupling. Herein, a defect engineering strategy for incorporating copper sites into the connected nodes of defective metal–organic framework UiO‐66‐NH2 for selective overall photo‐reduction of CO2 into acetone. The Cu2+ site in well‐modified CuN2O2 units served as a trapping site to capture electrons via efficient electron‐hole separation, forming the active Cu+ site for CO2 reduction. Two NH2 groups in CuN2O2 unit adsorb CO2 and cooperated with copper ion to functionalize as a triple atom catalytic site, each interacting with one CO2 molecule to strengthen the binding of *CO intermediate to the catalytic site. The deoxygenated *CO attached to the Cu site interacted with *CH3 fixed at one amino group to form the key intermediate CO*‐CH3, which interacted with the third reduction intermediate on another amino group to produce acetone. Our photocatalyst realizes efficient overall CO2 reduction to C3 product acetone CH3COCH3 with an evolution rate of 70.9 μmol gcat−1 h−1 and a selectivity up to 97 % without any adducts, offering a promising avenue for designing triple‐atomic sites to producing C3 product from photosynthesis with water. [ABSTRACT FROM AUTHOR]

Single‐atom nanozyme (SAzyme) has sparked increasing interest for catalytic antitumor treatment due to their more tunable and diverse active sites than natural metalloenzymes in complex physiological conditions. However, it is usually a hard task to precisely conduct catalysis at tumor sites after intravenous injection of those SAzyme with high reactivity. Moreover, the explorations of SAzymes in the anticancer application are still in its infancy and need to be developed. Herein, an in situ synthesis strategy for Cu SAzyme was constructed to convert adsorbed copper ions into isolated atoms anchored by oxygen atoms (Cu−O2/Cu−O4) via GSH‐responsive deformability of supports. Our results suggest that the in situ activation process could further facilitate the dissociation of copper ions and the consumption of glutathione, thereby leading to copper deposition in cytoplasm and triggering cuproptosis. Moreover, the in situ synthesis of Cu SAzyme with peroxidase‐like activity enabled the intracellular reactive oxygen species production, resulting in specifically disturbance of copper metabolism pathway. Meanwhile, the in situ exposed glucose transporter (GLUT) inhibitor phloretin (Ph) can block the glycose uptake to boost cuproptosis efficacy. Overall, this in situ activation strategy effectively diminished the off‐target effects of SACs‐induced catalytic therapies and introduced a promising treatment paradigm for advancing cuproptosis‐associated therapies. [ABSTRACT FROM AUTHOR]

Selective photoreduction of CO2 to multicarbon products, is an important but challenging task, due to high CO2 activation barriers and insufficient catalytic sites for C−C coupling. Herein, a defect engineering strategy for incorporating copper sites into the connected nodes of defective metal–organic framework UiO‐66‐NH2 for selective overall photo‐reduction of CO2 into acetone. The Cu2+ site in well‐modified CuN2O2 units served as a trapping site to capture electrons via efficient electron‐hole separation, forming the active Cu+ site for CO2 reduction. Two NH2 groups in CuN2O2 unit adsorb CO2 and cooperated with copper ion to functionalize as a triple atom catalytic site, each interacting with one CO2 molecule to strengthen the binding of *CO intermediate to the catalytic site. The deoxygenated *CO attached to the Cu site interacted with *CH3 fixed at one amino group to form the key intermediate CO*‐CH3, which interacted with the third reduction intermediate on another amino group to produce acetone. Our photocatalyst realizes efficient overall CO2 reduction to C3 product acetone CH3COCH3 with an evolution rate of 70.9 μmol gcat−1 h−1 and a selectivity up to 97 % without any adducts, offering a promising avenue for designing triple‐atomic sites to producing C3 product from photosynthesis with water. [ABSTRACT FROM AUTHOR]

Selective photoreduction of CO2 to multicarbon products, is an important but challenging task, due to high CO2 activation barriers and insufficient catalytic sites for C−C coupling. Herein, a defect engineering strategy for incorporating copper sites into the connected nodes of defective metal–organic framework UiO‐66‐NH2 for selective overall photo‐reduction of CO2 into acetone. The Cu2+ site in well‐modified CuN2O2 units served as a trapping site to capture electrons via efficient electron‐hole separation, forming the active Cu+ site for CO2 reduction. Two NH2 groups in CuN2O2 unit adsorb CO2 and cooperated with copper ion to functionalize as a triple atom catalytic site, each interacting with one CO2 molecule to strengthen the binding of *CO intermediate to the catalytic site. The deoxygenated *CO attached to the Cu site interacted with *CH3 fixed at one amino group to form the key intermediate CO*‐CH3, which interacted with the third reduction intermediate on another amino group to produce acetone. Our photocatalyst realizes efficient overall CO2 reduction to C3 product acetone CH3COCH3 with an evolution rate of 70.9 μmol gcat−1 h−1 and a selectivity up to 97 % without any adducts, offering a promising avenue for designing triple‐atomic sites to producing C3 product from photosynthesis with water. [ABSTRACT FROM AUTHOR]

Selective photoreduction of CO2 to multicarbon products, is an important but challenging task, due to high CO2 activation barriers and insufficient catalytic sites for C−C coupling. Herein, a defect engineering strategy for incorporating copper sites into the connected nodes of defective metal–organic framework UiO‐66‐NH2 for selective overall photo‐reduction of CO2 into acetone. The Cu2+ site in well‐modified CuN2O2 units served as a trapping site to capture electrons via efficient electron‐hole separation, forming the active Cu+ site for CO2 reduction. Two NH2 groups in CuN2O2 unit adsorb CO2 and cooperated with copper ion to functionalize as a triple atom catalytic site, each interacting with one CO2 molecule to strengthen the binding of *CO intermediate to the catalytic site. The deoxygenated *CO attached to the Cu site interacted with *CH3 fixed at one amino group to form the key intermediate CO*‐CH3, which interacted with the third reduction intermediate on another amino group to produce acetone. Our photocatalyst realizes efficient overall CO2 reduction to C3 product acetone CH3COCH3 with an evolution rate of 70.9 μmol gcat−1 h−1 and a selectivity up to 97 % without any adducts, offering a promising avenue for designing triple‐atomic sites to producing C3 product from photosynthesis with water. [ABSTRACT FROM AUTHOR]

A copper‐dependent self‐cleaving DNA (DNAzyme or deoyxyribozyme) previously isolated by in vitro selection has been analyzed by a combination of Molecular Dynamics (MD) simulations and advanced Electron Paramagnetic Resonance (Electron Spin Resonance) EPR/ESR spectroscopy, providing insights on the structural and mechanistic features of the cleavage reaction. The modeled 46‐nucleotide deoxyribozyme in MD simulations forms duplex and triplex sub‐structures that flank a highly conserved catalytic core. The DNA self‐cleaving construct can also form a bimolecular complex that has a distinct substrate and enzyme domains. The highly dynamic structure combined with an oxidative site‐specific cleavage of the substrate are two key‐aspects to elucidate. By combining EPR/ESR spectroscopy with selectively isotopically labeled nucleotides it has been possible to overcome the major drawback related to the "metal‐soup" scenario, also known as "super‐stoichiometric" ratios of cofactors versus substrate, conventionally required for the DNA cleavage reaction within those nucleic acids‐based enzymes. The focus on the endogenous paramagnetic center (Cu2+) here described paves the way for analysis on mixtures where several different cofactors are involved. Furthermore, the insertion of cleavage reaction within more complex architectures is now a realistic perspective towards the applicability of EPR/ESR spectroscopic studies. [ABSTRACT FROM AUTHOR]

Biodegradable stents have paved the way to treat coronary artery disease. However, rapid reendothelialization is required to solve the problems of mismatched degradation rates, localized inflammation, and insufficient biocompatibility. Herein, a novel passivated protein‐adsorption coating is synthesized by coordination chelation, oxidation, cross‐linking, polymerization, and deposition of dopamine, (‐)‐epigallocatechin gallate (EGCG), and copper ions (Cu2+) using two‐electron oxidation. This coating exhibits hierarchical functionality, that is, at the macroscale, its superhydrophilicity conveys antifouling ability; whereas at the microscale, the active groups (quinone‐, amino‐, hydroxyphenyl groups and aromatic ring) facilitate protein adsorption. Antifouling ability prevents acute thrombosis and inflammation and maintains initial microenvironment stability post‐implantation. The active groups facilitate gradual endothelial cells (ECs) adhesion. Meanwhile, the decomposition of nitric oxide (NO) donors to release NO is catalyzed by Cu2+, and EGCG alleviates or prevents oxidative stress damage, inflammatory responses, thrombosis formation, and excessive smooth muscle cells proliferation in the stent microenvironment. This provides favorable conditions for the rapid and healthy growth of ECs. This study proposes a novel strategy for rapid neointima formation comprising healthy ECs on the surfaces of biodegradable stents by depositing a passivated protein‐adsorption coating (polydopamine/EGCG/Cu), opening new possibilities for the efficient treatment of coronary artery disease. [ABSTRACT FROM AUTHOR]

L‐3,4‐dihydroxyphenylalanine (levodopa or L–DOPA) a precursor of neurotransmitter dopamine, has been universally prescribed as a gold standard for treatment of Parkinson's Disease (PD). However, direct administration of L–DOPA has risky adverse effects which makes it challenging in the treatment of PD. Hence developing simple detection platform for sensing of L–DOPA is significant. In this work, we have developed cysteine stabilized copper nanocluster quenched with Fe2+ (Fe2+@cys@CuNC) and used as both fluorescent and colorimetric probe for detection of L–DOPA. L–DOPA attributed a fluorescence quenching effect on developed probe. Fe2+@cys@CuNC detected L–DOPA within a linear range from 0.06 mM to 1.31 mM with a low limit of detection (LoD) of 6.57 nM. The probe also exhibited high selectivity for L–DOPA over other biomolecules and neurotransmitters. Furthermore, the capability of this probe was validated by sensing L–DOPA from human serum with excellent recovery rates of 85.75 % to 115.07 %. A low‐cost paper strip‐based portable detection platform was also developed for visual detection of L–DOPA. [ABSTRACT FROM AUTHOR]

The effects of heavy metals such as Hg(II) and Pb(II) on the human body are profound. Moreover, they pose significant concerns due to industrial development. Thus, the rapid and stable detection of heavy metal ions and related chemicals has emerged as an urgent issue. The application of Differential Pulse Stripping Voltammetry (DPSV) facilitated accurate and rapid detection of Hg2+ utilizing MOF materials and ZIF‐8 as detection agents. Pure ZIF‐8 served as the substrate material. Copper or nickel ions were individually introduced into the substrate material. This process resulted in the formation of bimetallic MOF materials. These materials were designated as CuZn and NiZn, respectively. Transition metal‐doped materials were used to modify the glassy carbon electrode (GCE), resulting in a substantial enhancement in the detection performance of Hg2+. The CuZn/GCE configuration demonstrated the most significant enhancement. When compared to a GCE modified with pure ZIF‐8, both sensitivity and the detection limit for free Hg2+ in the environment experienced increases of 450% and 64%, respectively. Stability and repeatability tests were conducted on the CuZn‐modified GCE. Results indicated that the electrode proved to be very stable and showed strong selectivity in the presence of interfering ions. The sensor modified with CuZn shows promising potential for monitoring trace Hg2+ levels. [ABSTRACT FROM AUTHOR]

Lysyl oxidase‐like 2 (LOXL2) is a Cu2+‐dependent amine oxidase that catalyzes the oxidative deamination of lysine residues of elastin and collagen to generate aldehyde groups. In the active state of LOXL2, its conserved catalytic domain has a lysine tyrosylquinone (LTQ) cofactor and a copper ion. LTQ is post‐translationally derived from Lys653 and Tyr689 of LOXL2. In this study, well‐tempered metadynamics simulations are used to investigate the conformation modulation from the inactive state to active state and obtain the free energy landscape. Interestingly, the simulations show that LTQ precursor residues cannot get close in Zn2+−bound LOXL2, whereas the copper ion binding triggers a conformation change to form an optional structure for LTQ biosynthesis. It is found that a prominent loop, consisting of residues 654–658, hinders the formation of LTQ in Zn2+−LOXL2 by preventing Lys653 from moving into active site of LOXL2, whereas this loop is relatively flexible in Cu2+−LOXL2. After the formation of LTQ, it needs to be activated by adjusting its position to be exposed to the solvent, thus allowing it to react with its substrate proteins. The results indicate that this process involves an intermediate state and that the activation of LTQ overcomes an energy barrier of 5.9 kcal mol−1. [ABSTRACT FROM AUTHOR]

To solve the problem of the presence of heavy metals in water causing water pollution, the biodegradable film based on zein/polyvinyl alcohol (PVA) with the incorporation of nano‐hydroxyapatite (nHAP) was fabricated through an electrospinning technique. The copper ion was taken as the representative of heavy metal ions in this study. The result showed that the incorporated nHAP nanoparticles were dispersed within the zein/PVA matrix, and strong hydrogen bonding interactions were formed between the filler and matrix, improving the hydrophobicity of the nanofibrous films and maintaining thermal stability. The adsorption mechanism was analyzed by fitting the adsorption process with pseudo‐first‐order model and pseudo‐second‐order model. Based on the ion exchange effect, electrostatic interaction, and complexation, the adsorption capacities of nanofibrous films for Cu(II) were significantly increased after adding nHAP. When the nHAP content was 20 wt.%, the Cu(II) adsorption capacity reached up to 23.86 mg/g, and the adsorption efficiency was 13.94% higher than that of neat zein/PVA nanofibers. This work suggests the potential of the electrospun zein/PVA/nHAP nanofibrous films as desirable eco‐friendly materials in metal removal applications. [ABSTRACT FROM AUTHOR]

Copper is a crucial catalyst in the synthesis of graphdiyne (GDY). However, as catalysts, the final fate of the copper ions has hardly been concerned, which are usually treated as impurities. Here, it is observed that after simple washing with water and ethanol, GDY still contains a certain amount of copper ions, and demonstrated that the copper ions are adsorbed at the atomic layers of GDY. Furthermore, we transformed in situ the copper ions into ultrathin Cu nanocrystals, and the obtained Cu/GDY hybrids can be generally converted into a series of metal/GDY hybrid materials, such as Ag/GDY, Au/GDY, Pt/GDY, Pd/GDY, and Rh/GDY. The Cu/GDY hybrids exhibit extraordinary surface enhanced Raman scattering effect and can be applied in pollutant efficient enrichment and detection. [ABSTRACT FROM AUTHOR]

High‐efficient photoelectrocatalytic direct ammonia oxidation reaction (AOR) conducted on semiconductor photoanodes remains a substantial challenge. Herein, we develop a strategy of simply introducing ppm levels of Cu ions (0.5–10 mg/L) into NH3 solutions to significantly improve the AOR photocurrent of bare BiVO4 photoanodes from 3.4 to 6.3 mA cm−2 at 1.23 VRHE, being close to the theoretical maximum photocurrent of BiVO4 (7.5 mA cm−2). The surface charge‐separation efficiency has reached 90 % under a low bias of 0.8 VRHE. This AOR exhibits a high Faradaic efficiency (FE) of 93.8 % with the water oxidation reaction (WOR) being greatly suppressed. N2 is the main AOR product with FEs of 71.1 % in aqueous solutions and FEs of 100 % in non‐aqueous solutions. Through mechanistic studies, we find that the formation of Cu−NH3 complexes possesses preferential adsorption on BiVO4 surfaces and efficiently competes with WOR. Meanwhile, the cooperation of BiVO4 surface effect and Cu‐induced coordination effect activates N−H bonds and accelerates the first rate‐limiting proton‐coupled electron transfer for AOR. This simple strategy is further extended to other photoanodes and electrocatalysts. [ABSTRACT FROM AUTHOR]

BACKGROUND: Phenolic acids are widespread in foods and are beneficial to human health. However, the role of metal ions in influencing the binding of proteins with phenolic acids that contain the same parent nucleus structure remains unclear. This study investigated the inhibitory effect of caffeic acid (CA) and chlorogenic acid (CHA) on α‐glucosidase and the biological effect of copper on this process. RESULTS: It was found that the esterification of CA with quinic acid could increase the fluorescence quenching, conformational change, and inhibitory effect of CHA on α‐glucosidase. Copper ions reduced their fluorescence quenching and conformation‐changing ability by binding to the neighboring phenolic hydroxyl group but also increased their ability to alter secondary structure and to inhibit α‐glucosidase and in vitro anti‐glycation. CONCLUSION: Overall, this study shows that the binding of copper ions to the phenolic hydroxyl group adjacent to CA and CHA synergistically inhibited α‐glucosidase. The findings will offer a theoretical basis for investigating the properties of metal ions and phenolic acid in food chemistry and their potential applications in the prevention and treatment of diabetes mellitus. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In this study, a naked‐eye colorimetric probe (L) was synthesized by condensation reaction of 9‐fluorenone with 2‐thiophene carboxylic acid hydrazide and characterized by various analytical techniques. The presence of O, N, and S heteroatoms in L would modulate the hard and soft characters, which is responsible for selective complexation of Cu2+ and fluorenone act as signalling unit. The sensing ability of L was studied with various metal ions by colorimetric, test paper strip, and UV‐visible spectrophotometry in DMSO: H2O (6 : 4, v/v). The colorless solution L turned green upon interacting with Cu2+ ions, while other ions did not change color. The probe L exhibits an absorbance band at 354 nm; upon interaction with Cu2+ ions, it exhibits a band at 413 nm due to ligand‐to‐metal charge transfer (LMCT). The probe L binds Cu2+ in a 2 : 1 stoichiometric ratio with an association constant of 3.76×107 M−2, established using Job's and BindFit methods. Further, binding mechanism is supported by EPR and ESI studies. The probe L can work in the pH range of 3.0 to 7.5 and detect as low as 93 nM (6 ppb) by spectrophotometry. Probe L demonstrates a promising potential for detecting Cu2+ ions in the semi‐aqueous medium. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the most common form of dementia worldwide, affecting millions of people around the globe. AD is characterized by different pathologies being beta‐amyloid (Aβ) plaque formation, metal ion dysregulation, and oxidative stress (OS) central topics under investigation. Copper‐Aβ complexes have been shown to induce catalytic hydrogen peroxide formation and increase OS in the brain leading to neuronal death. Pincer‐type compounds are tridentate ligands that coordinate metals in a planar fashion whose properties can be tuned via group substitutions, giving rise to many possibilities in catalysis and drug discovery. In this work we evaluated the potential pharmaceutical activity of 26 pincer compounds in AD's copper ion‐related oxidative stress framework. In this sense, four key aspects were considered: 1) Lipinski's rule of five, 2) blood‐brain barrier permeation, 3) standard reduction potential (SRP) of the formed copper complexes, and 4) the ligand's affinity towards copper cations. The evaluation of these criteria was performed by means of bioinformatic tools and electronic structure calculations at the DFT level of theory. Our results suggest that two compounds from this set are potential antioxidant agents, whereas five of them are promissory distributor‐like compounds in the context of AD. [ABSTRACT FROM AUTHOR]

With the aim of constructing hydrogen‐bonding networks in synthetic complexes, two new ligands derived from cis,cis‐1,3,5‐triaminocyclohexane (TACH) have been prepared that feature pendant pyrrole or indole rings as outer‐sphere H‐bond donors. The TACH framework offers a facial arrangement of three N‐donors, thereby mimicking common coordination motifs in the active sites of nonheme Fe and Cu enzymes. X‐ray structural characterization of a series of CuI‐X complexes (X=F, Cl, Br, NCS) revealed that these neutral ligands (H3LR, R=pyrrole or indole) coordinate in the intended facial N3 manner, yielding four‐coordinate complexes with idealized C3 symmetry. The N−H units of the outer‐sphere heterocycles form a hydrogen‐bonding cavity around the axial (pseudo)halide ligand, as verified by crystallographic, spectroscopic, and computational analyses. Treatment of H3Lpyrrole and H3Lindole with divalent transition metal chlorides (MIICl2, M=Fe, Cu, Zn) causes one heterocycle to deprotonate and coordinate to the M(II) center, giving rise to tetradentate ligands with two remaining outer‐sphere H‐bond donors. Further ligand deprotonation is observed upon reaction with Ni(II) and Cu(II) salts with weakly coordinating counteranions. The reported complexes highlight the versatility of TACH‐based ligands with pendant H‐bond donors, as the resulting scaffolds can support multiple protonation states, coordination geometries, and H‐bonding interactions. [ABSTRACT FROM AUTHOR]

Advanced oxidation processes using photogenerated charges in semiconductors constitute an approach to reduce and oxidize pollutants, with an efficiency that depends on the photo physics and defect chemistry of the photocatalyst. In this study, 2D Cu2O coatings on flat copper metal and on 3D copper nanopillars are created via low‐temperature oxidation and compared. The structures are characterized by X‐ray diffraction, Raman spectroscopy, and electron microscopy. The thickest surface oxide layers on the 3D structures show outgrowth of high‐aspect ratio CuO nano‐needles through the Cu2O layer, rationalized through a field‐induced copper ion diffusion mechanism. Raman scattering provides details about both the specific copper oxide phase present and the type and extent of defects, with a resolution spanning from hundreds of nanometers to micrometers. We show that defects in Cu2O induce Raman activity in several of its modes that are purely IR‐active or optically silent in pristine Cu2O. The experimental results are corroborated by linear response density functional theory (DFT) calculations for full vibrational mode analysis. The Cu‐supported 2D copper oxide systems exhibit effective photocatalytic performance at quite low probe pollution concentration (10 μM), while the 3D nanopillar structures enhance the photocatalytic efficiency by around 30 % compared to their planar counterpart under these conditions. [ABSTRACT FROM AUTHOR]

Although the multiple functional groups in biomass offer notable chances for producing high‐value chemicals, most of the current studies focused on the (deep) defunctionalization of biomass and its derivates. Herein, we present a catalytic approach to valorize birch wood lignin with maintaining the methoxy and hydroxy groups in the final product (i. e. 2,6‐dimethoxy‐p‐aminophenol), which has applications in different sectors such as pharmaceuticals. The proved approach involves four steps with a high yield (19.8 wt % on the basis of used lignin) to 2,6‐dimethoxy‐p‐aminophenol. The native lignin in birch wood was first converted using alkaline aerobic oxidation in the presence of copper ions toward high‐yield syringaldehyde, which was then selectively oxidized toward 2,6‐dimethoxy‐1,4‐benzoquinone using H2O2 and V2O5. Oximation of 2,6‐dimethoxy‐1,4‐benzoquinone can selectively form 2,6‐dimethoxy‐1,4‐benzoquinone‐4‐oxime, which can be quantitatively hydrogenated toward 2,6‐dimethoxy‐p‐aminophenol. This work highlights the unique potential of biomass and its derivates for the sustainable production of high‐value products with exploring the value of inherent functional groups. [ABSTRACT FROM AUTHOR]

Slight modification of the molten salt synthesis of poly(triazine imide) (PTI) with introduction of copper (I) chloride yielded a novel copper modified material. Energy‐dispersive x‐ray spectroscopy together with electron microscopy confirmed homogenous distribution of the copper within PTI lattice. X‐ray photoelectron spectroscopy suggests the copper to coordinate randomly at bridging nitrogen atoms. Thus obtained material exhibited excellent sensitivity to nitrite anions together with low limits of detection. Under previously optimized experimental conditions and pH 4 of supporting electrolyte, differential pulse voltammetric detection method showed linear response in wide range from 5 to 2200 μM with detection limit of 1.3 μM. Practical applicability for the developed method was scrutinized in wastewater and pipe water samples. Developed method of metal ion intercalation open doors to widespread introduction of metal ions in the PTI structure for practical utilization. [ABSTRACT FROM AUTHOR]

A copper ion imprinted chitosan flocculant (Cu2+@CTS) was synthesized by the molecular imprinting technique to improve the flocculation selectivity of chitosan to heavy metal ions. The effects of the amount of crosslinking agent, crosslinking time, temperature on the properties of the material were systematically investigated. Under the optimum preparation conditions, the flocculation rate and removal rate of Cu2+@CTS were 98.26% and 88.4%, respectively, 2.85 and 3.86 times higher than that of the unprinted chitosan flocculant. On this basis, the flocculation selectivity of Cu2+@CTS to Cu2+ in the presence of Zn2+, Ni2+ and other competitive ions was further explored. The experimental results indicated the removal rate of Cu2+ by Cu2+@CTS was as high as 70%–85%, which was 2.2–2.7 times that of other ions, while the removal rate of three metal ions by non‐imprinted chitosan flocculants was less than 35%. This study provided a reference for improving the selectivity of chitosan‐based flocculant to Cu2+. [ABSTRACT FROM AUTHOR]

Both hydrogen (H2) and copper ions (Cu+) can be used as anti‐cancer treatments. However, the continuous generation of H2 molecules and Cu+ in specific sites of tumors is challenging. Here we anchored Cu2+ on carbon photocatalyst (Cu@CDCN) to allow the continuous generation of H2 and hydrogen peroxide (H2O2) in tumors using the two‐electron process of visible water splitting. The photocatalytic process also generated redox‐active Cu‐carbon centers. Meanwhile, the Cu2+ residues reacted with H2O2 (the obstacle to the photocatalytic process) to accelerate the two‐electron process of water splitting and cuprous ion (Cu+) generation, in which the Cu2+ residue promoted a pro‐oxidant effect with glutathione through metal‐reducing actions. Both H2 and Cu+ induced mitochondrial dysfunction and intracellular redox homeostasis destruction, which enabled hydrogen therapy and cuproptosis to inhibit cancer cell growth and suppress tumor growth. Our research is the first attempt to integrate hydrogen therapy and cuproptosis using metal‐enhanced visible solar water splitting in nanomedicine, which may provide a safe and effective cancer treatment. [ABSTRACT FROM AUTHOR]

Methanobactin OB3b (Mbn‐OB3b) is a unique natural product with stunning affinity for copper ions (Ka≈Cu(I) 1034). Here, we report the first total synthesis of Cu(I)‐bound methanobactin OB3b featuring as key transformations a cyclodehydration‐thioacylation sequence, to generate the conjugated heterocyclic systems, and a copper‐templated cyclization, to complete the caged structure of the very sensitive target compound. [ABSTRACT FROM AUTHOR]

Covalent regulatory systems of enzymes are widely used to modulate biological enzyme activities. Inspired by the regulation of reactive‐site phosphorylation in organisms, we developed peptide‐based catecholase mimetics with switchable catalytic activity and high selectivity through the co‐assembly of nanofibers comprising peptides and copper ions (Cu2+). Through careful design and modification of the peptide backbone structure based on the change in the free energy of the system, we identified the peptide with the most effective reversible catalytic activity. Kinase/phosphatase switches were used to control the reversible transition of nanofiber formation and depolymerization, as well as to modulate the active‐site microenvironment. Notably, the self‐assembly and disassembly processes of nanofibers were simulated using coarse‐grained molecular dynamics. Furthermore, theoretical calculations confirmed the coordination of the peptide and Cu2+, forming a zipper‐like four‐ligand structure at the catalytically active center of the nanofibers. Additionally, we conducted a comprehensive analysis of the catalytic mechanism. This study opens novel avenues for designing biomimetic enzymes with ordered structures and dynamic catalytic activities. [ABSTRACT FROM AUTHOR]