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The development of physically crosslinked hydrogels with excellent mechanical and sensing properties is of importance for expanding the practical applications of intelligent soft hydrogel materials. Herein, after copolymerization of hydroxyl-containing amino acid derivative N-acryloyl serine (ASer) with acrylamide (AM), we introduce Zr4+ through an immersion strategy to construct metal ion-toughened non-covalent crosslinked hydrogels (with tensile strength of up to 5.73 MPa). It is found that the synergistic coordination of hydroxyl and carboxyl groups with Zr4+ substantially increases the crosslinking density of the hydrogels, thereby imparting markedly superior mechanical properties compared to hydroxyl-free Zr4+-crosslinked hydrogels, such as N-acryloyl alanine (AAla) copolymerized with AM hydrogels (with tensile strength of 2.98 MPa). Through the adjustment of the composition of the copolymer and the density of coordination bonds, the mechanical properties of the hydrogels can be modulated over a wide range. Additionally, due to the introduction of metal ions and the dynamic nature of coordination bonds, the hydrogels also exhibit excellent sensing performance and good self-recovery properties, paving the way for the development of flexible electronic substrates with outstanding comprehensive performances. [ABSTRACT FROM AUTHOR]

Transition metal coordination polymers (TM‐CP) are promising inexpensive and flexible electrocatalysts for oxygen evolution reaction in water electrolysis, while their facile synthesis and controllable regulation remain challenging. Here we report an anodic oxidation‐electrodeposition strategy for the growth of TM‐CP (TM=Fe, Co, Ni, Cr, Mn; CP=polyaniline, polypyrrole) films on a variety of metal substrates that act as both catalyst supports and metal ion sources. An exemplified bimetallic NiFe‐polypyrrole (NiFe‐PPy) features superior mechanical stability in friction and exhibits high activity with long‐term durability in alkaline seawater (over 2000 h) and anion exchange membrane electrolyzer devices at current density of 500 mA cm−2. Spectroscopic and microscopic analysis unravels the configurations with atomically distributed metal sites induced by d‐π conjugation, which transforms into a mosaic structure with NiFe (oxy)hydroxides embedded in PPy matrix during oxygen evolution. The superior catalytic performance is ascribed to the anchoring effect of PPy that inhibits metal dissolution, the strong substrate‐to‐catalyst interaction that ensures good adhesion, and the Fe/Ni−N coordination that modulates the electronic structures to facilitate the deprotonation of *OOH intermediate. This work provides a general strategy and mechanistic insight into building robust inorganic/polymer composite electrodes for oxygen electrocatalysis. [ABSTRACT FROM AUTHOR]

Folic acid (FA) is an essential vitamin involved in crucial metabolic processes, while copper(II) ions play significant roles in various biological functions. This study aims to investigate the interaction between FA and Cu2+ using 1H and 13C NMR spectroscopy under different pH levels and concentrations. The research employed detailed NMR analysis to explore how Cu2+ binds to FA, focusing on changes in chemical shifts, diffusion coefficients, and copper-induced paramagnetic effects. The key findings reveal that Cu2+ predominantly coordinates with the pteridine ring (PTE) of FA, with minimal involvement from the glutamic acid (Glu) moiety. The interaction is strongly concentration-dependent: at lower FA concentrations, Cu2+ binds effectively to the PTE ring, while at higher concentrations, intermolecular interactions among FA molecules hinder copper binding. The study also observed pronounced paramagnetic effects on the PTE and p-aminobenzoic acid protons, with negligible effects on Glu signals. These results provide new insights into the structural characteristics of FA-Cu2+ complexes, contributing to a better understanding of their biochemical interactions and implications for folate metabolism. [ABSTRACT FROM AUTHOR]

DNA molecules have excellent molecular recognition abilities through the complementary hydrogen-bonded base pairing. Since the hybridization of oligonucleotides can be programmed based on the sequences of the nucleobases, a great number of DNA supramolecular architectures have been constructed via self-assembly processes. The development of stimuli-responsive DNA supramolecules has attracted increasing interests because it will contribute to the construction of dynamic molecular systems such as molecular machines. Metal ions are considered as useful chemical stimuli, but the construction of metal-responsive DNA systems is still in the early stage. This review article describes current progress on the development of DNA supramolecules whose structure and function can be regulated in response to metal ions, with mainly focusing on our recent studies. The basic strategy is the introduction of unnatural metal ligands that form interstrand metal complexes in DNA structures. For example, artificial metal-mediated base pairs, formed through complexation between ligand-type nucleobase analogs and a bridging metal ion, were incorporated into known DNAzymes (catalytic DNA) to allosterically regulate their activity in a metal-responsive manner. Novel ligand-type nucleobases that form both metal-mediated and hydrogen-bonded base pairs have been recently devised as metal-responsive building blocks, and were used to construct a simple prototype of DNA molecular machines. Branched DNA structures bearing metal ligands at the junction core were also synthesized as novel structural motifs, with which metal-mediated structure transformation was demonstrated. These metal-responsive DNA supramolecules are expected to expand the toolbox of DNA-based supramolecular chemistry and nanotechnology. [ABSTRACT FROM AUTHOR]

The design of efficient, stable, low‐cost non‐precious metal‐based electrocatalysts with enhanced oxygen reduction reaction (ORR) activity has garnered significant attention in the scientific community. This study introduces a novel electrocatalyst, Fe/Co‐N‐MWCNT, synthesized through the in‐situ growth of ZIF‐8 and Fe/Co‐Phen on multi‐walled carbon nanotubes (MWCNTs), followed by pyrolysis at varying temperatures to optimize its properties. The inclusion of Fe and Co during the pyrolysis process facilitated the creation of metal active sites and Fe−Co, enhancing electron transfer and ORR activity. Compared to Pt/C (E1/2=0.854 V, JL=4.90 mA cm−2), Fe/Co‐N‐MWCNT exhibited a similar half‐wave potential (E1/2=0.812 V) and an improved limiting current density (JL=5.37 mA cm−2). Moreover, Fe/Co‐N‐MWCNT displayed remarkable stability, showing only a 7 mV negative shift in E1/2 after 2000 cycles. Ampere response testing indicated a current decay of only 7.8 % for Fe/Co‐N‐MWCNT after 10000 s, while Pt/C experienced a decay of about 18.4 %. The exceptional catalytic stability of Fe/Co‐N‐MWCNT positions it as a promising candidate for rechargeable zinc‐air batteries, attributed to its high pyridinic nitrogen content, unique structure, and abundant metal active sites. [ABSTRACT FROM AUTHOR]

Furosemide (FUR), banned in sports events by the World Anti‐Doping Agency, is a key target in drug tests, necessitating a pretreatment material capable of selectively, rapidly, and sufficiently separating/enriching analytes from complex matrices. Herein, a metal‐mediated magnetic molecularly imprinted polymer (mMIP) was rationally designed and synthesized for the specific capture of FUR. The preparations involved the utilization of chromium (III) as the binding pivot, (3‐aminopropyl)triethoxysilane as functional monomer, and Fe3O4 as core, all assembled via free radical polymerization. Both the morphologies and adsorptive properties of the mMIP were characterized using multiple methods. The resulting Cr(III)‐mediated mMIP (ChM‐mMIP) presented excellent selectivity and specificity toward FUR. Under optimized conditions, the adsorption capacity reached 128.50 mg/g within 10 min, and the imprinting factor was 10.41. Moreover, it was also successfully applied as a dispersive solid‐phase extraction material, enabling the detection of FUR concentration as low as 20 ng/mL in human urine samples when coupled with a high‐performance liquid chromatography/photodiode array. Overall, this study offers a valuable strategy for the development of novel recognition material. [ABSTRACT FROM AUTHOR]

Mussel byssus offers bio‐inspired designs for advanced adhesives, coatings, and supramolecular hydrogels. Solidification of secreted proteins into mechanically robust fibers is triggered by a pH jump from acidic fluid condensates to basic seawater conditions driving protein crosslinking by metal coordination with 3,4‐dihydroxyphenylalanine (DOPA). Knowledge of the dynamic and localized pH changes during secretion is currently lacking. Yet, this information is crucial for controlling the gelation and properties of mussel‐inspired DOPA‐modified materials. Here, an iridium oxide‐based pH microsensor combining high mechanical stability and spatial resolution is used to measure the acidic pH during byssus secretion and to map mussel‐inspired hydrogels revealing compositional heterogeneity resulting in mechanically distinct regions. Within the hydrogel, high pH values >12 are measured which are detrimental to DOPA due to its strong propensity for oxidation, which adversely alters gel properties. This demonstrates the need to improve preparation methods of mussel‐inspired adhesive materials to more closely mimic native processes. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An innovative amino acid-based metallo-supramolecular nanoassembly with POD- and GSHOx-like activities was designed for tumoricidal chemo-/photo-/catalytic combination therapy. [Display omitted] Nanozymes, as nanomaterials with natural enzyme activities, have been widely applied to deliver various therapeutic agents to synergistically combat the progression of malignant tumors. However, currently common inorganic nanozyme-based drug delivery systems still face challenges such as suboptimal biosafety, inadequate stability, and inferior tumor selectivity. Herein, a super-stable amino acid-based metallo-supramolecular nanoassembly (FPIC NPs) with peroxidase (POD)- and glutathione oxidase (GSHOx)-like activities was fabricated via Pt4+-driven coordination co-assembly of l -cysteine derivatives, the chemotherapeutic drug curcumin (Cur), and the photosensitizer indocyanine green (ICG). The superior POD- and GSHOx-like activities could not only catalyze the decomposition of endogenous hydrogen peroxide into massive hydroxyl radicals, but also deplete the overproduced glutathione (GSH) in cancer cells to weaken intracellular antioxidant defenses. Meanwhile, FPIC NPs would undergo degradation in response to GSH to specifically release Cur, causing efficient mitochondrial damage. In addition, FPIC NPs intrinsically enable fluorescence/photoacoustic imaging to visualize tumor accumulation of encapsulated ICG in real time, thereby determining an appropriate treatment time point for tumoricidal photothermal (PTT)/photodynamic therapy (PDT). In vitro and in vivo findings demonstrated the quadruple orchestration of catalytic therapy, chemotherapeutics, PTT, and PDT offers conspicuous antineoplastic effects with minimal side reactions. This work may provide novel ideas for designing supramolecular nanoassemblies with multiple enzymatic activities and therapeutic functions, allowing for wider applications of nanozymes and nanoassemblies in biomedicine. [ABSTRACT FROM AUTHOR]

Responsive hydrogels hold great promise for applications such as biological tissue engineering, controlled drug release, soft actuators, and intelligent sensors. However, the design and construction of robust responsive hydrogels using a simple method remains a significant challenge. Herein, a non‐covalently crosslinked responsive hydrogel was constructed by introducing carboxyl‐Zr4+ metal coordination to the hydrophobic association network of P(AA‐co‐LMA) hydrogel through a facile one‐pot polymerization method. The incorporation of multiple reversible interactions, including hydrogen bonding, metal coordination, and hydrophobic association, resulted in a responsive hydrogel with exceptional mechanical strength (≈2.92 MPa), outstanding flexibility (elongation>1000%), and rapid response to pH alterations. Furthermore, the hydrogel also presented good ionic conductivity due to the abundant movable ions, as well as high sensitivity and stability. As application demonstrations, the supermolecular hydrogel had been successfully used in actuating and strain sensing. This work establishes an effective design strategy for creating tough and multifunctional responsive hydrogel. [ABSTRACT FROM AUTHOR]

In metal coordination compounds of the divergent ligands 4,2′:6′,4"‐terpyridine and 3,2′:6′,3"‐terpyridine and their 4′‐functionalized derivatives, the central pyridine ring of the 4,2′:6′,4"‐terpyridine and 3,2′:6′,3"‐terpyridine domains is non‐coordinated. We present an overview of data from the Cambridge Structural Database to assess whether there are structural similarities between the coordination compounds of 4,2′:6′,4"‐tpy and 1,3‐di(pyridin‐4‐yl)benzene, and between 3,2′:6′,3"‐tpy and 1,3‐di(pyridin‐3‐yl)benzene. Based upon structurally characterized compounds, it emerges that the coordination chemistry of ligands including one or more 4,2′:6′,4"‐terpyridine or 3,2′:6′,3"‐terpyridine metal‐binding domains is more abundantly exemplified than that of corresponding ligands based upon 1,3‐di(pyridin‐4‐yl)benzene and 1,3‐di(pyridin‐3‐yl)benzene. We provide an overview of metallamacrocycles and cages, 1D‐coordination polymers and 2D‐ and 3D‐networks. [ABSTRACT FROM AUTHOR]

As protein crystals are increasingly finding diverse applications as scaffolds, controlled crystal polymorphism presents a facile strategy to form crystalline assemblies with controllable porosity with minimal to no protein engineering. Polymorphs of consensus tetratricopeptide repeat proteins with varying porosity were obtained through co‐crystallization with metal salts, exploiting the innate metal ion geometric requirements. A single structurally exposed negative amino acid cluster was responsible for metal coordination, despite the abundance of negatively charged residues. Density functional theory calculations showed that while most of the crystals were the most thermodynamically stable assemblies, some were kinetically trapped states. Thus, crystalline porosity diversity is achieved and controlled with metal coordination, opening a new scope in the application of proteins as biocompatible protein‐metal‐organic frameworks (POFs). In addition, metal‐dependent polymorphic crystals allow direct comparison of metal coordination preferences. [ABSTRACT FROM AUTHOR]

Structures held together by secondary interactions such as intramolecular or intermolecular hydrogen bonding, electrostatic and π–π interaction without covalent bonds can exhibit new properties such as high orientation, optoelectronics, biocompatibility and reversibility (self‐renewal). Recently, interest has been growing surrounding novel molecules fashioned through non‐covalent interactions. These molecules have garnered attention due to their significant roles in both physical and chemical applications. However, the formation of complexes between cationic phenothiazine derivative dyes, commonly employed in electrochemical studies, and diverse metal groups presents a challenge. Therefore, the existing literature contains only a scant number of studies concerning the formation of phenothiazine complexes with metal salts. In this study, metal complexes of thionine, azure C and azure A with copper(II) chloride were prepared using two steps: dissolving and then slow evaporation of dyes‐copper(II) chloride in acetonitrile. Besides the theoretical computations, thermal, spectral, electrochemical and fluorescence techniques were performed to determine the characteristics of the monoclinic crystals of Cu–dyes complexes. Cl− ion in the dyes and copper(II) chloride conjugated to form [CuCl3]−, then this anion electrostatically bound to cationic phenothiazine ring bond to be phenothiazine+[CuCl3]−. Cu–dye complexes showed interestingly high electron transportation. In addition, prepared Cu–dye complexes have a great potential to be used in optical and spectral applications with extraordinary behaviour of their spectral and fluorescence features. [ABSTRACT FROM AUTHOR]

The poor film stability of Sn-Pb mixed perovskite film and the mismatched interface energy levels pose significant challenges in enhancing the efficiency of tin–lead (Sn-Pb) mixed perovskite solar cells. In this study, polyvinylpyrrolidone (PVP) is introduced into the PVK perovskite precursor solution, effectively enhancing the overall stability of the film. This improvement is achieved through the formation of robust coordination bonds between the carbonyl (C=O) in the pyrrole ring and the undercoordinated SnII and PbII, thereby facilitating the passivation of defects. Furthermore, the introduction of PVP inhibits the oxidation of tin (Sn), thereby enhancing the n-type characteristics of the perovskite film. This adjustment in the energy level of the PVK perovskite film proves instrumental in reducing interface energy loss, subsequently improving interface charge transfer and mitigating device recombination. Consequently, perovskite solar cells incorporating PVP achieve an outstanding champion power conversion efficiency (PCE) of 21.31%. [ABSTRACT FROM AUTHOR]

Folic acid (FA) is an essential vitamin involved in crucial metabolic processes, while copper(II) ions play significant roles in various biological functions. This study aims to investigate the interaction between FA and Cu2+ using 1H and 13C NMR spectroscopy under different pH levels and concentrations. The research employed detailed NMR analysis to explore how Cu2+ binds to FA, focusing on changes in chemical shifts, diffusion coefficients, and copper-induced paramagnetic effects. The key findings reveal that Cu2+ predominantly coordinates with the pteridine ring (PTE) of FA, with minimal involvement from the glutamic acid (Glu) moiety. The interaction is strongly concentration-dependent: at lower FA concentrations, Cu2+ binds effectively to the PTE ring, while at higher concentrations, intermolecular interactions among FA molecules hinder copper binding. The study also observed pronounced paramagnetic effects on the PTE and p-aminobenzoic acid protons, with negligible effects on Glu signals. These results provide new insights into the structural characteristics of FA-Cu2+ complexes, contributing to a better understanding of their biochemical interactions and implications for folate metabolism.

Electro‐fabrication is an emerging additive manufacturing approach that includes a variety of mechanisms and crosslinking chemistries to induce the self‐assembly‐ of soft matter. Within electro‐fabrication techniques, anodic electro‐fabrication is of great interest, because it can use the electrode as a sacrificial source of metal ions for the controlled formation of chelated hydrogels. However, it remains challenging to understand how the various solution conditions (e.g., buffer capacity, ligands) and imposed voltages must be controlled to achieve the chelation and sol‐gel transition. Herein, a comprehensive thermodynamics‐based framework is built to guide the selection of conditions for the self ‐assembly of polysaccharide hydrogels by crosslinking with transition metal ions generated via corrosion. This methodology is demonstrated through real‐time spectro‐electrochemical monitoring and employed for the electro‐fabrication of chitosan hydrogels chelated with Au3+, Ag+, Cu2+, and Pd2+, and alginate hydrogels chelated with Cu2+. The presented guidelines are intended to extend the capabilities of the controlled fabrication of assemblies crosslinked with metal ions, opening new horizons for unprecedented materials design with precisely tailored structures and functions. [ABSTRACT FROM AUTHOR]

Over the last 15 years, the byssus of marine mussels (Mytilus spp.) has emerged as an important model system for the bio-inspired development and synthesis of advanced polymers and adhesives. But how did these seemingly inconsequential fibers that are routinely discarded in mussel hors d’oeuvres become the focus of intense international research. In the present review, we take a historical perspective to understand this phenomenon. Our purpose is not to review the sizeable literature of mussel-inspired materials, as there are numerous excellent reviews that cover this topic in great depth. Instead, we explore how the byssus became a magnet for bio-inspired materials science, with a focus on the specific breakthroughs in the understanding of composition, structure, function, and formation of the byssus achieved through fundamental scientific investigation. Extracted principles have led to bio-inspired design of novel materials with both biomedical and technical applications, including surgical adhesives, self-healing polymers, tunable hydrogels, and even actuated composites. Continued study into the byssus of Mytilid mussels and other species will provide a rich source of inspiration for years to come.

Abstract Electro‐fabrication is an emerging additive manufacturing approach that includes a variety of mechanisms and crosslinking chemistries to induce the self‐assembly‐ of soft matter. Within electro‐fabrication techniques, anodic electro‐fabrication is of great interest, because it can use the electrode as a sacrificial source of metal ions for the controlled formation of chelated hydrogels. However, it remains challenging to understand how the various solution conditions (e.g., buffer capacity, ligands) and imposed voltages must be controlled to achieve the chelation and sol‐gel transition. Herein, a comprehensive thermodynamics‐based framework is built to guide the selection of conditions for the self ‐assembly of polysaccharide hydrogels by crosslinking with transition metal ions generated via corrosion. This methodology is demonstrated through real‐time spectro‐electrochemical monitoring and employed for the electro‐fabrication of chitosan hydrogels chelated with Au3+, Ag+, Cu2+, and Pd2+, and alginate hydrogels chelated with Cu2+. The presented guidelines are intended to extend the capabilities of the controlled fabrication of assemblies crosslinked with metal ions, opening new horizons for unprecedented materials design with precisely tailored structures and functions.

Chemotherapy is commonly used to treat cancer. However, insufficient retention at the target site and systemic toxicity remains critical challenges. Chitosan has attracted considerable attention as a carrier backbone for delivering therapeutic cargos because of its biocompatibility and mucoadhesive property. However, pH and concentration-dependent solubility of chitosan has been restricted further applications to clinical settings. Inspired by marine mussels and crustaceans, in this study, we present chitosan-based nanoparticles containing catechol–Fe3+ complexes (Cat-CS NPs) as a tumor-activatable delivery system to achieve highly efficient locoregional treatment of cancer via a simple spray process while minimizing adverse effects towards surrounding normal tissues. Cat-CS NPs were fabricated through electrospraying and exhibited superior adhesiveness on substrates in aqueous conditions in a surface-independent manner. The pH-responsive stoichiometry of catechol–Fe3+ coordination in doxorubicin (DOX)-loaded Cat-CS NPs (Cat-CS@DOX NPs) enabled a triggered release of DOX in response to acidic conditions around tumor tissues. The sprayed Cat-CS@DOX NPs significantly inhibited cancer cell growth in vitro while exhibiting good biocompatibility towards normal cells. Taken together, Cat-CS NP-based sprayable nanotherapeutics can be used as a locoregional delivery system, especially in adjuvant cancer therapy. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Histidine–M2+ coordination bonds are a recognized bond motif in biogenic materials with high hardness and extensibility, which has led to growing interest in their use in soft materials for mechanical function. However, the effect of different metal ions on the stability of the coordination complex remains poorly understood, complicating their implementation in metal‐coordinated polymer materials. Herein, rheology experiments and density functional theory calculations are used to characterize the stability of coordination complexes and establish the binding hierarchy of histamine and imidazole with Ni2+, Cu2+, and Zn2+. It is found that the binding hierarchy is driven by the specific affinity of the metal ions to different coordination states, which can be macroscopically tuned by changing the metal‐to‐ligand stoichiometry of the metal‐coordinated network. These findings facilitate the rational selection of metal ions for optimizing the mechanical properties of metal‐coordinated materials. [ABSTRACT FROM AUTHOR]

Achieving on‐demand control of responsive behaviors of photochromic molecules is important for advanced photonic applications, but it remains a challenge. In this work, a triphenylethylene‐based molecule, 5‐(2,2‐bis(4‐fluorophenyl)vinyl)‐5″‐methyl‐2,2″‐bipyridine (1), which can undergo open‐to‐closed isomerization under 365 nm irradiation, is designed and synthesized. Importantly, on‐demand acceleration or deceleration of photoisomerization rate over a wide range (kUV = 0.00584–0.06299 s−1) is achieved by coordination of 1 with different metal salts. Furthermore, more precise manipulation of the photoisomerization rate is achieved by changing the counterions of the 1‐based metal complex. Eventually, taking advantage of distinctly different photoisomerization rates of 1 and its corresponding metal complexes, high‐level irradiation time‐dependent information encryption and anticounterfeiting applications have been demonstrated. [ABSTRACT FROM AUTHOR]

Bispidines are a family of ligands that plays a pivotal role in various areas of coordination chemistry, with applications in medicinal chemistry, molecular catalysis, coordination polymers synthesis, and molecular magnetism. In the present work, triazole moieties were introduced using the CuAAC click-reaction, with the aim of expanding the number of coordination sites on the bispidine core. The 1,2,3-triazole rings were thus synthesized on propargyl-derived bispidines after reaction with different alkyl azides. The new class of triazole-bispidines was characterized, and their chelation capabilities were evaluated with different metals through NMR titration, ESI-MS spectrometry, and single-crystal X-ray diffraction (SC-XRD). Finally, the suitability of these molecules as metal ligands for the catalytic Henry reaction was demonstrated with copper and zinc. [ABSTRACT FROM AUTHOR]

Sphingan WL gum produced by marine Sphingomonas sp. WG is a new kind of extracellular polysaccharide reported by our group in 2016. This work selected five metal ions, Na+, Zn2+, Ca2+, Cu2+, and Fe3+, to prepare sphingan WL gum-metal ion (WL-M) composite hydrogels by immersion-adsorption method for the first time. With the increase of immersion solution concentration, the volume of WL-M shrinks, the water content decreases, and the content of metal ions increases. WL-Na2, with the highest water content (91.81%), has the lowest metal ion content (20.76 mg/g); WL-Cu4, with the highest metal ion content (99.80 mg/g), has the lowest water content (73.07%). The results of inductively coupled plasma optical emission spectroscopy show that the adsorption capacity (mg/g) of metal ions by WL is in the order of Cu2+ > Zn2+ > Fe3+ > Ca2+ > Na+. Fourier transform infrared and X-ray photoelectron spectroscopy results suggest that carboxyl and hydroxyl groups are the main active sites of WL interacting with metal ions. The rheological test results reveal that the order of cross-linking effect is Ca2+ > Fe3+ > Cu2+ > Zn2+ > Na+. The G' of WL-Ca4 is the largest, reaching 154.9 Pa at 1 rad/s. The metal ion release behavior was found to follow the Korsmeyer-Peppas model (R2 > 0.97, n < 0.43) and be pH responsive. WL-Ca3 shows good biocompatibility, self-healing, and injectable properties. The above results indicate that the WL-Ca hydrogels have the most promising application prospects in biomedicine and deserve further research. [ABSTRACT FROM AUTHOR]

Hierarchical Ce-containing TS-1 catalysts were successfully prepared by combining the skeleton metal doping and alkali treatment strategies. The amount of metal doping and alkali solution concentration were adjusted to optimize the ratio of samples. The modified samples were characterized by using various techniques such as XRD, SEM, TEM, and XPS, which revealed that the modified samples contained 2–4 nm mesopores with a grain size of about 150 nm. The positive relationship between the amount of Ce doped and the cell parameters confirms the successful doping of Ce into the TS-1 zeolite skeleton. Furthermore, the modified molecular sieves showed weaker acidity and stronger hydrophobicity. Then, the experiments to evaluate the epoxidation reaction of hierarchical TS-1 molecular sieve containing Ce on long-chain olefins (n-pentene, n-hexene) as well as cyclic olefins (cyclopentene, cyclohexene) were investigated using H2O2 as the oxidant. The modified samples exhibited higher conversion of large olefins and selectivity of epoxides compared with untreated TS-1. Therefore, the accessibility of the active center after the complex modification and the synergistic catalytic effect of the metal Ti with Ce can be verified. On this basis, the catalyst was tested in batch operation for five cycles to investigate the reusability performance, and the results showed a slight decrease in yield. After roasting at 550 °C, the initial catalytic activity of the previous cycle was fully recovered. This study provides an inexpensive catalyst for the epoxidation of long-chain olefins, laying the foundation for its commercial application. Preparation method and epoxidation reaction route of hierarchieal cerium containing TS-1 catalyst. [ABSTRACT FROM AUTHOR]

• The complex affinity with FQs has an order of Fe(III) > Cu(II) > Al(III). • Photochemistry properties of FQs were affected by metal complexation. • FQs-Cu(II) complex was verified by FTIR and theory of electrostatic potential. • Significant changes in toxicity of antibiotics were found after metal coordination. Acid-base dissociable antibiotic-metal complexes are known to be emerging contaminants in the aquatic environments. However, little information is available on the photochemical properties and toxicity of these complex forms. This study investigated the spectral properties of three fluoroquinolones (FQs) with and without metal ions Fe(III), Cu(II), and Al(III) in solutions under different pH conditions, as well as evaluated the changes in toxicity due to the complex with these metal ions using luminescent bacteria (vibrio fischeri). FQs showed a higher tendency to coordinate metal ions under alkaline conditions compared to neutral and acidic conditions, and the formation of complexes weakened the ultraviolet-absorbing ability of FQs. At pH = 7.0, Cu(II) quenched the fluorescence intensity of FQs. Moreover, their Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy were explored, revealing that the coordination sites of Cu(II) in three FQs were situated in a bidentate manner through the oxygen atom of the deprotonated carboxyl group and cyclic carbonyl oxygen atom. This conclusion was further verified by the theory of molecular surface electrostatic potential. In addition, except for complexes of ciprofloxacin-metals, enhanced toxicity of FQs upon coordination with Fe(III) was observed, while reduced toxicity was found for coordination with Cu(II) and Al(III). These results are important for accurately evaluating the photochemical behavior and risk of these antibiotics in aquatic environments contaminated with metal ions. [Display omitted] [ABSTRACT FROM AUTHOR]

The poor film stability of Sn-Pb mixed perovskite film and the mismatched interface energy levels pose significant challenges in enhancing the efficiency of tin–lead (Sn-Pb) mixed perovskite solar cells. In this study, polyvinylpyrrolidone (PVP) is introduced into the PVK perovskite precursor solution, effectively enhancing the overall stability of the film. This improvement is achieved through the formation of robust coordination bonds between the carbonyl (C=O) in the pyrrole ring and the undercoordinated SnII and PbII, thereby facilitating the passivation of defects. Furthermore, the introduction of PVP inhibits the oxidation of tin (Sn), thereby enhancing the n-type characteristics of the perovskite film. This adjustment in the energy level of the PVK perovskite film proves instrumental in reducing interface energy loss, subsequently improving interface charge transfer and mitigating device recombination. Consequently, perovskite solar cells incorporating PVP achieve an outstanding champion power conversion efficiency (PCE) of 21.31%.

The neutral N‐heterocyclic carbene stabilized bora‐alkene 1, conveniently prepared by a BH borenium/hydroboration route, forms stable copper, gold or palladium π‐complexes. The polar bora‐alkene B=C system undergoes regioselective hydroboration reactions with the (C6F5)2BH or C6F5BH2 ⋅ SMe2 boranes. The latter reaction involves a subsequent rearrangement that leads to internal hydride vs. isothiocyanate substituent exchange at the borane pair. [ABSTRACT FROM AUTHOR]

Energy dissipation based on dynamic fracture of metal ligands is an effective way to toughen hydrogels for specific applications in biomedical and engineering fields. Exploration of new kinds of metal‐ligand coordinates with robust bonding strength is crucial for the facile synthesis of tough gels. Here a hydrogel toughening strategy based on the formation of robust coordination complexes between the hydrazide ligands and zinc ions is reported. The resultant hydrogels exhibit high strength and toughness at room temperature. Their mechanical properties show temperature dependence due to the dynamic nature of coordination bonds. In addition, the amine group of hydrazides in the gel matrix provides a reactive site for Schiff's base reaction, enabling surface modification without influence on overall mechanical performances of the gel. The hydrazide ligands are easy to synthesize and can coordinate very well with several transition metals. Such a metal‐ligand coordination should be suitable to develop tough soft materials with versatile applications. [ABSTRACT FROM AUTHOR]

Therapeutic drug monitoring of captopril, which is a commonly used antihypertensive agent in clinical practice, is necessary. However, matrix effect‐induced pretreatment is the bottleneck for determination. Metal‐mediated molecularly imprinted polymers, an essential branch of molecularly imprinted polymers with better specificity and selectivity, have been used to separate/enrich analytes from complex matrices. In this work, Cu2+ was introduced to dynamically establish the binding sites of metal‐mediated molecularly imprinted polymer towards captopril. All evidence demonstrated that the metal‐mediated molecularly imprinted polymer based on Cu2+ coordination obtained a higher adsorption capacity (81.23 mg/g), faster adsorption rate (adsorption equilibrium within 50 min), and better selectivity (with the unrecognized analog). Subsequently, the Cu2+‐mediated molecularly imprinted polymer was used as dispersive molecularly imprinted solid‐phase extraction to successfully establish an analytical platform for the determination of trace captopril in rat plasma. The enrichment factor was up to 20, the detection limit was as low as 0.16 μg/ml, and the average recovery was in the range of 87.51%–98.28% with a relative standard deviation of less than 3.29%. This study provides a promising reference for the preparation of selective adsorbents to improve pretreatment. [ABSTRACT FROM AUTHOR]

Histidine and cysteine residues, with their imidazole and thiol moieties that deprotonate at approximately physiological pH values, are primary binding sites for Zn(II), Ni(II) and Fe(II) ions and are thus ubiquitous both in peptidic metallophores and in antimicrobial peptides that may use nutritional immunity as a way to limit pathogenicity during infection. We focus on metal complex solution equilibria of model sequences encompassing Cys–His and His–Cys motifs, showing that the position of histidine and cysteine residues in the sequence has a crucial impact on its coordination properties. CH and HC motifs occur as many as 411 times in the antimicrobial peptide database, while similar CC and HH regions are found 348 and 94 times, respectively. Complex stabilities increase in the series Fe(II) < Ni(II) < Zn(II), with Zn(II) complexes dominating at physiological pH, and Ni(II) ones—above pH 9. The stabilities of Zn(II) complexes with Ac-ACHA-NH2 and Ac-AHCA-NH2 are comparable, and a similar tendency is observed for Fe(II), while in the case of Ni(II), the order of Cys and His does matter—complexes in which the metal is anchored on the third Cys (Ac-AHCA-NH2) are thermodynamically stronger than those where Cys is in position two (Ac-ACHA-NH2) at basic pH, at which point amides start to take part in the binding. Cysteine residues are much better Zn(II)-anchoring sites than histidines; Zn(II) clearly prefers the Cys–Cys type of ligands to Cys–His and His–Cys ones. In the case of His- and Cys-containing peptides, non-binding residues may have an impact on the stability of Ni(II) complexes, most likely protecting the central Ni(II) atom from interacting with solvent molecules. [ABSTRACT FROM AUTHOR]

Inositol poly- and pyrophosphates (InsPs and PP-InsPs) are central eukaryotic messengers. These very highly phosphorylated molecules can exist in two distinct conformations, a canonical one with five phosphoryl groups in equatorial positions, and a "flipped" conformation with five axial substituents. Using 13C-labeled InsPs/PP-InsPs, the behavior of these molecules was investigated by 2D-NMR under solution conditions reminiscent of a cytosolic environment. Remarkably, the most highly phosphorylated messenger 1,5(PP)2-InsP4 (also termed InsP8) readily adopts both conformations at physiological conditions. Environmental factors—such as pH, metal cation composition, and temperature—strongly influence the conformational equilibrium. Thermodynamic data revealed that the transition of InsP8 from the equatorial to the axial conformation is, in fact, an exothermic process. The speciation of InsPs and PP-InsPs also affects their interaction with protein binding partners; addition of Mg2+ decreased the binding constant Kd of InsP8 to an SPX protein domain. The results illustrate that PP-InsP speciation reacts very sensitively to solution conditions, suggesting it might act as an environment-responsive molecular switch. [ABSTRACT FROM AUTHOR]

Here, we describe the recent progress on metal‐coordinated supramolecular structures with unique characteristics and controlled helicity based on coordination geometry and dynamic intermolecular binding events. The current major research area is the self‐assembly of a metal‐containing molecule into nanomaterials. It generated a large number of supramolecular polymers, which have various structures and functions. Although the dynamic coordination complexation reactions between various metal ions and ligands are spontaneous, we successfully achieved unique morphological transformations with helical inversion of metal‐containing supramolecular polymers via the kinetic control of dynamic coordination complexation reactions. Our findings have a significant impact on the development of novel and advanced supramolecular materials, and dynamic coordination bonds in the molecular design of metal‐containing complexes for modulating self‐assembly pathways, which may be relevant for the fabrication of supramolecular materials with interesting properties. Our contributions may be useful to the understanding of chiral assembly processes in biological systems. [ABSTRACT FROM AUTHOR]

Recently, the well-characterized metallodrug auranofin has been demonstrated to restore the penicillin and cephalosporin sensitivity in resistant bacterial strains via the inhibition of the NDM-1 beta-lactamase, which is operated via the Zn/Au substitution in its bimetallic core. The resulting unusual tetrahedral coordination of the two ions was investigated via the density functional theory calculations. By assessing several charge and multiplicity schemes, coupled with on/off constraining the positions of the coordinating residues, it was demonstrated that the experimental X-ray structure of the gold-bound NDM-1 is consistent with either Au(I)-Au(I) or Au(II)-Au(II) bimetallic moieties. The presented results suggest that the most probable mechanism for the auranofin-based Zn/Au exchange in NDM-1 includes the early formation of the Au(I)-Au(I) system, superseded by oxidation yielding the Au(II)-Au(II) species bearing the highest resemblance to the X-ray structure. [ABSTRACT FROM AUTHOR]

Metal ions play critical roles in facilitating peptide folding and inducing conformational transitions, thereby impacting on the biological activity of many proteins. However, the effect of metal sites on the hierarchical structures of biopolymers is still poorly understood. Herein, inspired by metalloproteins, we report an order‐to‐order conformational regulation in synthetic polymers mediated by a variety of metal ions. The copolymers are decorated with clinically available desferrioxamine (DFO) as an exogenous ligand template, which presents a geometric constraint toward peptide backbone via short‐range hydrogen bonding interactions, thus dramatically altering the secondary conformations and self‐assembly behaviors of polypeptides and allowing for a controllable β‐sheet to α‐helix transition modulated by metal–ligand interactions. These metallopolymers could form ferritin‐inspired hierarchical structures with high stability and membrane activity for efficient brain delivery across the blood–brain barrier (BBB) and long‐lasting magnetic resonance imaging (MRI) in vivo. [ABSTRACT FROM AUTHOR]

Pollution of the aquatic environment by halogen derivatives widely used as antiseptic compounds, as well as chemicals for various industrial purposes, is significant. Existing systems of bioremediation poorly solve the problem of eliminating pollution. This paper discusses the preparation of novel macroporous chitosan-based cryogels with in situ-immobilized Pd or Pt nanoparticles as a catalyst for dichlorination reactions. The formation mechanism of metal coordinated chitosan gels using Medusa software modelling and rheology (G' and G") is discussed. Metal coordinated chitosan gels were subsequently converted into covalently cross-linked macroporous cryogels with in situ-immobilized Pd or Pt nanoparticles using the redox potentials difference of the reaction mixture. Noble metal nanoparticles of average size, 2.4 nm, were evenly distributed in the cryogel structure. The effectiveness of these gels as a catalyst for the decomposition of chloro-compounds o-chlorophenol, p-chlorophenol and 2,4-dichlorophenol was tested. The catalytic hydrogenation reaction was carried out using the "green reducing agent" formic acid. Increasing the excess of formic acid with heating increases the degree of conversion up to 80–90%. The CHI-GA-PdNPs cryogel at pH 6 showed better efficiency in the hydrogenation process compared to the CHI-GA-PtNPs cryogel; however, no significant difference in the degree of conversion at pH 3 was observed. The termination of a catalytic reaction in a batch mode have been studied. Several control tests were carried out to elucidate the mechanism of catalyst poisoning. The presented catalytic system may be of interest for studying reactions in a flow through mode, including the reactions for obtaining valuable chemicals. [ABSTRACT FROM AUTHOR]

We report the coordination assembly of the ferrocene-diphenylalanine (Fc-FF) with divalent copper ions (Cu2+) into metal-peptide assemblies (MPAs) with hierarchical spiral architectures. The MPA particles are composed of helically organized nanofibers which can be correlated to the logarithmic spirals. The MPAs are hierarchically porous with abundant Fc and Cu2+ active sites and show much higher catalytic activity than natural laccase toward the decolorization reaction. Moreover, a series of hierarchical structures of the MPAs can be synthesized by controlling the temperature and enantiomeric excess (ee). The peptide enantiomers with higher ee values will self-assemble into highly complex and ordered structures, which show higher surface area and porosity and thus enhanced catalytic activity compared with those assembled by peptides with lower ee values. The results provide new insights into the vital role of chirality in directing the self-assembly of biomolecules into highly ordered complex functional structures. [ABSTRACT FROM AUTHOR]

The chalcogen bond has been recently defined by the IUPAC as the attractive noncovalent interaction between any element of group 16 acting as an electrophile and any atom (or group of atoms) acting as a nucleophile. Commonly used chalcogen bond donor molecules are divalent selenium and tellurium derivatives that exhibit two σ-holes. In fact, the presence of two σ-hole confers to the chalcogen bonding additional possibilities with respect to the halogen bond, the most abundant σ-hole interaction. In this manuscript, we demonstrate that selenoxides are good candidates to be used as σ-hole donor molecules. Such molecules have not been analyzed before as chalcogen bond donors, as far as our knowledge extends. The σ-hole opposite to the Se=O bond is adequate for establishing strong and directional ChBs, as demonstrated herein using the Cambridge structural database (CSD) and density functional theory (DFT) calculations. Moreover, the effect of the metal coordination of the selenoxide to transition metals on the strength of the ChB interaction has been analyzed theoretically. The existence of the ChBs has been further supported by the quantum theory of atoms in molecules (QTAIM) and the noncovalent interaction plot (NCIPlot). [ABSTRACT FROM AUTHOR]

Rubber materials are widely used in aerospace, automotive, smart devices and artificial skin. It is significant to address the aging susceptibility of conventional vulcanized rubber and to impart it rapid self-healing performance for destructive crack damage. Herein, a novel supramolecular rubber elastomer is prepared by introducing metal coordination between carboxyl-terminated polybutadiene and polystyrene-vinylpyridine copolymer. Based on the metal coordination interaction, the elastomer exhibits shape memory and self-healing properties. Moreover, a rapid closure-repair process of destructive cracks is achieved by presetting temporary shapes. This shape memory-assisted self-repair model is shown to be an effective means for rapid repair of severe cracks. An approach to enhance the mechanical and self-healing properties of elastomer was demonstrated by adding appropriate amounts of oxidized carbon nano-onions (O-CNO) into the system. The tensile strength of the elastomer with an O-CNOs content of 0.5 wt% was restored to 83 ± 10% of the original sample after being repaired at 85 °C for 6 h. This study confirms that metal coordination interaction is an effective method for designing shape memory self-healing rubber elastomer. The shape memory-assisted self-healing effect provides a reference for the rapid self-repairing of severe cracks. [ABSTRACT FROM AUTHOR]

Folded molecules provide complex interaction interfaces amenable to sophisticated self‐assembly motifs. Because of their high conformational stability, aromatic foldamers constitute suitable candidates for the rational elaboration of self‐assembled architectures. Several multiturn helical aromatic oligoamides have been synthesized that possess arrays of acridine appendages pointing in one or two directions. The acridine units were shown to direct self‐assembly in the solid state via aromatic stacking leading to recurrent helix‐helix association patterns under the form of discrete dimers or extended arrays. In the presence of Pd(II), metal coordination of the acridine units overwhelms other forces and generates new metal‐mediated multihelical self‐assemblies, including macrocycles. These observations demonstrate simple access to different types of foldamer‐containing architectures, ranging from discrete objects to 1D and, by extension, 2D and 3D arrays. [ABSTRACT FROM AUTHOR]

[Display omitted] Histidine, a versatile proteinogenic amino acid, plays a broad range of roles in all living organisms and behaves as a key mediator of the interactions of biomolecules with inorganic constituents. The self-assembly of histidine-rich peptides and proteins is critical in biology, as the histidine unit is both a multifunctional regulator and an ideal motif for the construction of complex biological structures. In particular, non-covalent interactions between the imidazole ring and other molecular building blocks and metal ions are routinely employed to generate these complexes. Therefore, this strategy can be duplicated in an artificial context to create sophisticated bioactive materials. In this review, we first highlight a clear perspective of the bio-inspired design strategies which can replicate the hierarchical structure of biological systems allowing the engineering of the supramolecular self-assembly of histidine-functionalized peptides. We further summarize advancements in the field of peptide supramolecular structures incorporating histidine residues in the peptide backbone to generate organized functional supramolecular biomaterials with customizable features. We also discuss significant advances and future prospects in supramolecular self-assembly of histidine-functionalized peptides, as well as provide an overview of advanced techniques for the fabrication of histidine-based biomaterials for bio-nanotechnology, optoelectronic engineering, and biomedicine. Overall, artificial supramolecular materials based on histidine functionalized peptides, motivated by the intriguing properties discovered in natural proteins, bear the potential to boost the creation of sustainable bio-inspired materials. [ABSTRACT FROM AUTHOR]

Tissue defect is one of the significant challenges encountered in clinical practice. Nanomaterials, including nanoparticles, nanofibers, and metal-organic frameworks, have demonstrated an extensive potential in tissue regeneration, offering a promising avenue for future clinical applications. Nonetheless, the intricate landscape of the inflammatory tissue microenvironment has engendered challenges to the efficacy of nanomaterial-based therapies. This quandary has spurred researchers to pivot towards advanced nanotechnological remedies for overcoming these therapeutic constraints. Among these solutions, microenvironment-sensitive nanozymes have emerged as a compelling instrument with the capacity to reshape the tissue microenvironment and enhance the intricate process of tissue regeneration. In this review, we summarize the microenvironmental characteristics of damaged tissues, offer insights into the rationale guiding the design and engineering of microenvironment-sensitive nanozymes, and explore the underlying mechanisms that underpin these nanozymes' responsiveness. This analysis includes their roles in orchestrating cellular signaling, modulating immune responses, and promoting the delicate process of tissue remodeling. Furthermore, we discuss the diverse applications of microenvironment-sensitive nanozymes in tissue regeneration, including bone, soft tissue, and cartilage regeneration. Finally, we shed our sights on envisioning the forthcoming milestones in this field, prospecting a future where microenvironment-sensitive nanozymes contribute significantly to the development of tissue regeneration and improved clinical outcomes. This review article highlights recent representative research progresses using microenvironment-sensitive nanozymes for enhancing tissue regeneration. [Display omitted] [ABSTRACT FROM AUTHOR]

High-quality DNA is an important guarantee to start downstream experiments in many biological and medical research areas. Magnetic particle-based DNA extraction methods from blood mainly depend on electrostatic adsorption in a low-pH environment. However, the strong acidic environment can influence the DNA stability. Herein, a polydopamine-functionalized magnetic particle (PDA@Fe 3 O 4)-based protocol was developed for DNA extraction from whole blood samples. In the protocol, Mg2+ and Ca2+ were utilized to bridge the adsorption of DNA by PDA@Fe 3 O 4 via the metal-mediated coordination. Isopropanol was found to efficiently promote DNA adsorption by triggering the change of the conformation of DNA from B-form to more compact A-form. In 50 % isopropanol solution, the DNA adsorption efficiency was nearly 100 % in the presence of 0.5 mM Ca2+ or 1.5 mM Mg2+. The role of metal ions and isopropanol in DNA adsorption was explored. The protocol averts the strong acidic environment and PCR inhibitors, such as high concentrations of salt or polyethylene glycol. It demonstrates superiority in DNA yield (59.13 ± 3.63 ng μL−1) over the commercial kit (27.33 ± 4.98 ng μL−1) and phenol-chloroform methods (37.90 ± 0.47 ng μL−1). In addition, to simplify the operastion, an automated nucleic acid extraction device was designed and fabricated to extract whole genomic DNA from blood. The feasibility of the device was verified by extracting DNA from cattle and pig blood samples. The extracted DNA was successfully applied to discriminate the beef authenticity by a duplex PCR system. The results demonstrate that the DNA extraction protocol and the automated device have great potential in blood samples. [Display omitted] • PDA@Fe 3 O 4 was used to purify DNA from blood based on metal-mediated coordination. • Isopropanol promotes DNA adsorption by triggering the change of DNA conformation. • The protocol demonstrates absolute superiority in DNA yield over other methods. • An automated device was fabricated to simplify DNA extraction. • The platform combined with PCR was applied to identify beef authenticity. [ABSTRACT FROM AUTHOR]

Bispidines are a family of ligands that plays a pivotal role in various areas of coordination chemistry, with applications in medicinal chemistry, molecular catalysis, coordination polymers synthesis, and molecular magnetism. In the present work, triazole moieties were introduced using the CuAAC click-reaction, with the aim of expanding the number of coordination sites on the bispidine core. The 1,2,3-triazole rings were thus synthesized on propargyl-derived bispidines after reaction with different alkyl azides. The new class of triazole-bispidines was characterized, and their chelation capabilities were evaluated with different metals through NMR titration, ESI-MS spectrometry, and single-crystal X-ray diffraction (SC-XRD). Finally, the suitability of these molecules as metal ligands for the catalytic Henry reaction was demonstrated with copper and zinc.

Metal-coordination-directed macrocyclic complexes, in which macrocyclic architectures are formed by metal-ligand coordination interactions, have emerged as attractive supramolecular scaffolds for the creation of materials for applications in biosensing and therapeutics. Despite recent progress, uncontrolled multicyclic cages and linear oligomers/polymers is the most likely outcome from metal-ligands assembly, representing a challenge to current synthetic methods. Herein we outlined the state-of-art synthetic approaches to the metal-coordination-directed macrocyclic complexes by using foldable ligands or through assembly of amphiphilic ligands. This mini-review offers a guideline for the efficient preparation of metal-coordination-directed macrocyclic complexes with predictable and controllable structures, which may find applications in many biology-related areas.

Crosslinking plays a crucial role in determining mechanical properties of polymer materials. Although various crosslinks based on covalent or noncovalent bonds have been adopted, it remains an enormous challenge to develop a crosslink which could endow corresponding polymer network with robust yet dynamic properties. Herein, we report a crosslink simultaneously having dynamic property and woven geometry, and the polymer network with woven crosslinks (WPN) could integrate the merits of covalent polymer network (CPN) and supramolecular polymer network (SPN). In specific, the WPN not only exhibits comparable stiffness, strength, elastic recovery, and anti‐fatigue property to those of CPN, but also possesses decent mechanical adaptivity and ductility, similar to those of SPN. Particularly, its toughness and puncture resistance are much superior to those of the others. Besides, the dynamicity of woven crosslink also imparts good performances of self‐healing and processability to WPN. [ABSTRACT FROM AUTHOR]

[Display omitted] Hydrophilic-hydrophobic microphase separation is an important mechanism to promote aqueous polymer self-assembly. However, it is rarely used in the construction of magneto-dielectric absorbers in the interdisciplinary research involving organic polymer and inorganic hybrid material. Herein, a novel metal-coordination-driven self-assembly strategy is proposed for fabricating organic–inorganic composite co-assemblies by combining resorcinol–formaldehyde resin as carbon precursor and iron-containing polymer self-assemblies as soft template. Co-assemblies are then transformed into porous iron/carbon (Fe/C) composites with spherical Fe nanoparticles and micro-mesopores that form in graphited carbon matrix through high-temperature pyrolysis. The minimum reflection loss of Fe/C-800 composite in paraffin matrix with 10% filler loading can reach −57.8 dB, while the effective absorption bandwidth of 5.3 GHz can cover the whole X band. It is considered that the co-assemblies-derived microstructure and magneto-dielectric composition contribute to the multiple reflection, polarization loss, conductive loss, ferromagnetic resonance and eddy current loss for high-efficiency electromagnetic wave absorption. In general, this work opens up new prospects for designing and preparing high-performance magneto-dielectric absorbers via a novel metal-coordination-driven self-assembly strategy. [ABSTRACT FROM AUTHOR]

Liquid-liquid phase separation (LLPS) or biomolecular condensation that leads to formation of membraneless organelles plays a critical role in many biochemical processes. Mechanism study of regulating LLPS is therefore central to the understanding of protein aggregation and disease-relevant process. We report a fused in sarcoma protein (FUS)-derived low complexity (LC) sequence that undergoes LLPS in the presence of metal ions. The LC protein was constructed by fusing a hexhistidine-tag to the N-terminal low complexity domain (the residues 1–165 in QGSY-rich segment) of FUS. Spontaneous condensation of the intrinsic disordered protein into coacervate droplets was observed in the presence of metal ions that chelate oligohistidine moieties to form protein matrix. We demonstrate the key role of metal ion-histidine coordination in governing LLPS behaviours and the fluidity of biomolecular condensates. By taking advantage of competitive binding using chelators, we show the possibility of regulating dynamic behaviors of disease-relevant protein droplets, and developing a potential approach towards controllable biological encapsulation/release. [ABSTRACT FROM AUTHOR]