A supramolecular hydrogel leveraging hierarchical multi-strength hydrogen-bonds hinged strategy achieving a striking adhesive-mechanical balance.

To obtain high-performance tissue-adhesive hydrogel embodying excellent mechanical integrity, a supramolecular hydrogel patch is fabricated through in situ copolymerization of a liquid-liquid phase separation precursor composed of self-complementary 2-2-ureido-4-pyrimidone-based monomer and acrylic acid coupled with subsequent corporation of bioactive epigallocatechin gallate. Remarkably, the prepared supramolecular hydrogel leverages hierarchical multi-strength hydrogen-bonds hinged strategy assisted by alkyl-based hydrophobic pockets, broadening the distribution of binding strength of physical junctions, striking a canonical balance between superb mechanical performance and robust adhesive capacity. Ultimately, the fabricated supramolecular hydrogel patch stands out as a high stretchability (1500 %), an excellent tensile strength (2.6 MPa), a superhigh toughness (12.6 MJ m-3), an instant and robust tissue adhesion strength (263.2 kPa for porcine skin), the considerable endurance under cyclic loading and reversible adhesion, a superior burst pressure tolerance (108 kPa) to those of commercially-available tissue sealants, and outstanding anti-swelling behavior. The resultant supramolecular hydrogel patch demonstrates the rapid hemorrhage control within 60 s in liver injury and efficient wound closure and healing effects with alleviated inflammation and reduced scarring in full-thickness skin incision, confirming its medical translation as a promising self-rescue tissue-adhesive patch for hemorrhage prevention and sutureless wound closure.

Boosting supercapacitive performance of pristine covalent organic frameworks via phenolic hydroxyl groups: A two-in-one strategy.

Two-dimensional covalent organic frameworks (COFs) are ideal electrode materials for electrochemical energy storage devices due to their unique structures and properties, and the accessibility and utilization efficiency of the redox-active sites within COFs are critical determinants of their pseudocapacitive performance. Via introducing meticulously designed phenolic hydroxyl (Ar-OH) groups with hydrogen-bond forming ability onto the imine COF skeletons, DHBD-Sb-COF exhibited improved hydrophilicity and crystallinity than the parent BD-Sb-COF, the redox-active sites (SbPh3 moieties) in COF electrodes could thus be highly accessed by aqueous electrolyte with a high active-site utilization of 93%. DHBD-Sb-COF//AC provided an excellent supercapacitive performance with an energy density of 78 Wh Kg-1 at the power density of 2553 W Kg-1 and super cycling stability, exceeding most of the previously reported pristine COF electrode-based supercapacitors. The "two-in-one" strategy of introducing hydroxyl groups onto imine COF skeletons to enhance both hydrophilicity and crystallinity provides a new avenue to improve the electrochemical performance of COF-based electrodes for high-performance supercapacitors.

Fluxional halogen bonds in linear complexes of tetrafluorodiiodobenzene with dinitrobenzene.

The fluxional nature of halogen bonds (XBs) in small molecular clusters, supramolecules, and molecular crystals has received considerable attention in recent years. In this work, based on extensive density-functional theory calculations and detailed electrostatic potential (ESP), natural bonding orbital (NBO), non-covalent interactions-reduced density gradient (NCI-RDG), and quantum theory of atoms in molecules (QTAIM) analyses, we unveil the existence of fluxional halogen bonds (FXBs) in a series of linear (IC6F4I)m(OONC6H4NOO)n (m + n = 2-5) complexes of tetrafluorodiiodobenzene with dinitrobenzene which appear to be similar to the previously reported fluxional hydrogen bonds (FHBs) in small water clusters (H2O)n (n = 2-6). The obtained GS ⇌ TS ⇌ GS ' $$ \mathrm{GS}\rightleftharpoons \mathrm{TS}\rightleftharpoons {\mathrm{GS}}^{\hbox{'}} $$ fluxional mechanisms involve one FXB in the systems which fluctuates reversibly between two linear CI···O XBs in the ground states (GS and GS') via a bifurcated CI O2N van der Waals interaction in the transition state (TS). The cohesive energies (Ecoh) of these complexes with up to four XBs exhibit an almost perfect linear relationship with the numbers of XBs in the systems, with the average calculated halogen bond energy of Ecoh/XB = 3.48 kcal·mol-1 in the ground states which appears to be about 55% of the average calculated hydrogen bond energy (Ecoh/HB = 6.28 kcal·mol-1) in small water clusters.

(E)-1-(3,4-Di-meth-oxy-phen-yl)-3-(1,3-diphenyl-1H-pyrazol-4-yl)prop-2-en-1-one.

In the title compound, C26H22N2O3, the dihedral angle between the benzene and pyrazole rings of the chalcone unit is 88.3 (1)°. The pyrazole ring has two attached phenyl rings that form dihedral angles with the pyrazole ring of 22.6 (2) and 40.0 (1)°. In the crystal, pairwise C-H⋯O hydrogen bonds generate R 2 2(20) inversion dimers.

Crystal structure, Hirshfeld surface analysis, DFT optimized mol-ecular structure and the mol-ecular docking studies of 1-[2-(cyano-sulfan-yl)acet-yl]-3-methyl-2,6-bis-(4-methyl-phen-yl)piperidin-4-one.

The two mol-ecules in the asymmetric unit of the title compound, C23H24N2O2S, have a structural overlap with an r.m.s. deviation of 0.82 Å. The piperidine rings adopt a distorted boat conformation. Intra- and inter-molecular C-H⋯O hydrogen bonds are responsible for the cohesion of the crystal packing. The inter-molecular inter-actions were qu-anti-fied and analysed using Hirshfeld surface analysis. The mol-ecular structure optimized by density functional theory (DFT) at the B3LYP/6-311++G(d,p)level is compared with the experimentally determined mol-ecular structure in the solid state.

8-Hy-droxy-quinolinium tri-chlorido-(pyridine-2,6-di-carb-oxy-lic acid-κ3 O,N,O')copper(II) dihydrate.

The title compound, (C9H8NO)[CuCl3(C7H5NO4)]·2H2O, was prepared by reacting CuII acetate dihydrate, solid 8-hy-droxy-quinoline (8-HQ), and solid pyridine-2,6-di-carb-oxy-lic acid (H2pydc), in a 1:1:1 molar ratio, in an aqueous solution of dilute hydro-chloric acid. The CuII atom exhibits a distorted CuO2NCl3 octa-hedral geometry, coordinating two oxygen atoms and one nitro-gen atom from the tridentate H2pydc ligand and three chloride atoms; the nitro-gen atom and one chloride atom occupy the axial positions with Cu-N and Cu-Cl bond lengths of 2.011 (2) Šand 2.2067 (9) Å, respectively. In the equatorial plane, the oxygen and chloride atoms are arranged in a cis configuration, with Cu-O bond lengths of 2.366 (2) and 2.424 (2) Å, and Cu-Cl bond lengths of 2.4190 (10) and 2.3688 (11) Å. The asymmetric unit contains 8-HQ+ as a counter-ion and two uncoordinated water mol-ecules. The crystal structure features strong O-H⋯O and O-H⋯Cl hydrogen bonds as well as weak inter-actions including C-H⋯O, C-H⋯Cl, Cu-Cl⋯π, and π-π, which result in a three-dimensional network. A Hirshfeld surface analysis indicates that the most important contributions to the crystal packing involving the main residues are from H⋯Cl/Cl⋯H inter-actions, contributing 40.3% for the anion. Weak H⋯H contacts contribute 13.2% for the cation and 28.6% for the anion.

Crystal structure of bis-(µ2-5-nona-noylquinolin-8-olato)bis-[aqua-dichlorido-indium(III)].

Crystallization of 5-nona-noyl-8-hy-droxy-quinoline in the presence of InCl3 in aceto-nitrile yields a dinuclear InIII complex crystallizing in the space group P. In this complex, [In2(C18H22NO2)2Cl4(H2O)2], each indium ion is sixfold coordinated by two chloride ions, one water mol-ecule and two 8-quinolino-late ions. The crystal of the title complex is composed of two-dimensional supra-molecular aggregates, resulting from the linkage of the Owater-H⋯O=C and Owater-H⋯Cl hydrogen bonds as well as bifurcated Carene-H⋯Cl contacts.

Regulating Intermolecular Hydrogen Bonds in Organic Cathode Materials to Realize Ultra-stable, Flexible and Low-temperature Aqueous Zinc-organic Batteries.

Rational design of molecular structures is one of the effective strategies to obtain high-performance organic cathode materials. However, besides the optimization of single-molecule structures, the influence of the "weak" interaction forces (e.g. hydrogen bonds) in organic cathode materials on the performance of batteries should be fully considered. Herein, three organic small molecules with different numbers of hydroxyl groups (namely nitrogen heterocyclic tetraketone (DAB), monohydroxyl nitrogen heterocyclic dione (HDA), dihydroxyl nitrogen heterocyclic dione (DHT)) were selected as the cathodes of aqueous zinc ion batteries (AZIBs), and the effect of the intermolecular hydrogen bonds on their electrochemical performance was studied for the first time. Clearly, the stable hydrogen-bond networks built through the hydroxyl groups significantly enhance the cycle stability of organic small-molecule cathodes and facilitate rapid proton conduction between the hydrogen-bond networks through the Grotthuss mechanism, thereby endowing them with excellent rate performance. In addition, a larger and more dense two-dimensional hydrogen-bond network can be constructed through multiple hydroxyl groups, further enhancing the structural stability of organic small-molecule cathodes, giving them better cycle tolerance, excellent rate performance, and extreme environmental tolerance.

New phase transition of p-cresol studied by DSC analysis and FT-IR spectroscopy.

We have investigated polymorphism in p-cresol using the FT-IR spectroscopy and differential scanning calorimetry. The present results show that in addition to the well-known two crystalline phases of p-cresol, which melts at 307.6 and 309.2 K, we discovered the existence of a new crystalline phase, which melts at 302.9 K. For the first time we have received the FT-IR spectra of three polymorphs and their temperature dependencies in the region 300-12 K. Comparison between the FT-IR spectra of three polymorphs shows that they are completely different.

Enabling High Strength and Toughness Polyurethane through Disordered-Hydrogen Bonds for Printable, Recyclable, Ultra-Fast Responsive Capacitive Sensors.

The rapid advancement of smart, flexible electronic devices has paralleled a surge in electronic waste (e-waste), exacerbating massive resource depletion and serious environmental pollution. Recyclable materials are extensively investigated to address these challenges. Herein, this study designs a unique polyurethane (SPPUs) with ultra-high strength up to 60 MPa and toughness of 360 MJ m-3. This synthetic SPPUs can be fully recycled at room temperature by using green solvents of ethanol. Accordingly, the resultant SPPU-Ni composites, created by mixing the ethanol-dissolved SPPUs solution with nickel (Ni) powder, effectively combine the flexibility and recyclability of SPPUs with the electrical conductivity of the nickel filler. Notably, this work develops the printable capacitive sensors (PCBS) through transcribing the paste of SPPUs-Ni slurry onto PET film and paper using screen-printing technology. The devised PCBS have fast response time ≈50 ms, high resolution, and multiple signal recognition capabilities. Remarkably, SPPUs and Ni powder can be fully recycled by only dissolving the waste PCBS in ethanol. This work offers a sustainable solution to the growing e-waste problem in recyclable flexible electronics.

Phonon Transport in Supramolecular Polymers Regulated by Hydrogen Bonds.

Supramolecular polymers hold promise in thermal management applications due to their multistability, high responsiveness, and cost-effectiveness. In this work, we successfully regulate phonon transport at the molecular level in supramolecular polymers by adjusting the strength of intermolecular hydrogen bonding. We synthesized three supramolecular polymer fibers with thermal conductivity differences of up to 289% based on melamine (M) and three simple positional isomers of hydroxybenzoic acid. Differential Scanning Calorimetry (DSC) measurement revealed discrepancies in thermal stability of the polymers, where structures with higher stability exhibited enhanced thermal conductivity. Fourier Transform Infrared Spectroscopy (FTIR) measurement and Density Functional Theory (DFT) calculations indicate that these differences arise from variations in hydrogen-bonding strengths at different bonding sites. Higher hydrogen-bonding strength leads to more stable thermal pathways, reduces phonon scattering, and increases thermal conductivity. Our findings provide valuable insights into controlling the thermal conductivity of polymer fibers, paving the way for applications in phonon-based thermal devices.

An Ultrastable Aqueous Ammonium-Ion Battery Using a Covalent Organic Framework Anode.

Aqueous ammonium ion batteries have garnered significant research interest due to their safety and sustainability advantages. However, the development of reliable ammonium-based full batteries with consistent electrochemical performance, particularly in terms of cycling stability, remains challenging. A primary issue stems from the lack of suitable anode materials, as the relatively large NH4 + ions can cause structural damage and material dissolution during battery operation. To address this challenge, an Aza-based covalent organic framework (COF) material is introduced as an anode for aqueous ammonium ion batteries. This material exhibits superior ammonium storage capabilities compared to existing anode materials. It operates effectively within a negative potential range of 0.3 to‒1.0 V versus SCE, achieves high capacity even at elevated current densities (≈74 mAh g-1 at 10 A g-1), and demonstrates exceptional stability, retaining a capacity over 20 000 cycles at 1.0 A g-1. Furthermore, by pairing this COF anode with a Prussian blue cathode, an ammonium rocking-chair full battery is developedd that maintains 89% capacity over 20 000 cycles at 1.0 A g-1, surpassing all previously reported ammonium ion full batteries. This study offers insights for the design of future anodes for ammonium ion batteries and holds promise for high-energy storage solutions.

Anomalous Pressure-Induced Blue-Shifted Emission of Ionic Copper-Iodine Clusters: The Competitive Effect between Coprophilic Interactions and Through-Space Interactions.

Developing ionic copper-iodine clusters with multiple emitting is crucial for enriching lighting and display materials with various colors. However, the luminescent properties of traditional ionic copper-iodine clusters are often closely associated with low-energy cluster-centered triplet emission, which will redshift further as the Cu···Cu bond length decreases. This article utilizes a pressure-treated strategy to achieve an anomalous pressure-induced blue-shifted luminescence phenomenon in ionic Cu4I6(4-dimethylamino-1-ethylpyridinium)2 crystals for the first time, which is based on dominant through-space charge-transfer (TSCT). Herein, we reveal that the more advantageous through-space interactions in the competition between coprophilic interactions and through-space interactions can lead to a blue-shifted luminescence. High-pressure angle-dispersive X-ray diffraction and high-pressure infrared experiments show that the enhanced through-space interactions mainly originate from forming new intermolecular C-H···I hydrogen bonds and the enhancement of van der Waals interactions between organic cations and anionic clusters. Theoretical calculations and experimental studies of excited-state dynamics confirm that the blue-shifted emission is due to the increased energy gap between the excited triplet and ground states caused by the electron delocalization under stronger through-space interactions. This work deepens previous understanding and provides a new avenue to design and synthetic ionic copper-iodine clusters with high-energy TSCT emission.

A Conserved Tryptophan (Trp10) at the Hydrophobic Core Modulates the Stability and Inhibitory Activity of Potato I Type Inhibitors.

BACKGROUND: Different inhibitor families have their own conserved three-dimensional structures, but how these structures determine whether a protein can become an inhibitor is still unknown. The buckwheat trypsin inhibitor (BTI) pertains to the Potato I type inhibitor family, which is a simple and essential bio-molecule that serves as a model for the investigation of protease-inhibitor interaction. OBJECTIVE: To: study the effects of mutations at Trp10 and Ile25 in the hydrophobic cavity(scaffold) of rBTI on its inhibitory activity and stability. METHODS: A site-directed mutagenesis and molecular modeling were performed using the sequence of BTI. The hydrogen bonds formed by all amino acids and conformational differences of Trp53 were analyzed in the tertiary structures of rBTI and mutants. RESULTS: Mutant rBTI-W10A almost completely lost its inhibitory activity (retaining 10%), while rBTI-I25A retained about 50% of its inhibitory activity. Both rBTI-W10A and rBTI-I25A could be degraded by trypsin. The hydrogen bond analysis results showed that mutating Trp10 or Ile25 weakened the specific cohesion interactions in the hydrophobic core of rBTI, disrupting the tight hydrogen bond network in the cavity. This further led to difficulty in maintaining the binding loop conformation, ultimately causing the Trp53 to undergo conformational changes. It was also difficult for residues in the mutants to form hydrogen bonds with amino acids in bovine trypsin; thus, the mutants could not stably bind to trypsin. CONCLUSION: Our findings suggest that the hydrophobic core is also an important factor in the maintenance of inhibitory activity and stability of rBTI.

Development of a New Permanganate/Chlorite Process for Water Decontamination.

Development of new technologies with strong selectivity for target pollutants and low sensitivity toward a water matrix remains challenging. Herein, we introduced a novel strategy that used chlorite as an activator for Mn(VII) at pH 4.8, turning the inert reactivity of the pollutants toward Mn(VII) into a strong reactivity. This paved a new way for triggering reactions in water decontamination. By utilizing sulfamethoxazole (SMX) as a typical pollutant, we proposed coupled pathways involving electron transfer across hydrogen bonds (TEHB) and oxidation by reactive manganese species. The results indicated that a hydrogen bonding complex, SMX-ClO2-*, formed through chlorite binding the amino group of SMX initially in the TEHB route; such a complex exhibited a stronger reduction capability toward Mn(VII). Chlorite, in the hydrogen bonding complex SMX-ClO2-*, can then complex with Mn(VII). Consequently, a new reactive center (SMX-ClO2--Mn(VII)*) was formed, initiating the transfer of electrons across hydrogen bonds and the preliminary degradation of SMX. This is followed by the involvement of the generated Mn(V)-ClO2-/Mn(III) in the reduction process of Mn(VII). Such a process showed pH-dependent degradation, with a removal ratio ranging from 80% to near-stagnation as pH increased from 4.8 to 7. Combining with pKa analysis showed that the predominant forms of contaminants were crucial for the removal efficiency of pollutants by the Mn(VII)/chlorite process. The impact of the water matrix was demonstrated to have few adverse or even beneficial effects. With satisfactory performance against numerous contaminants, this study introduced a novel Mn(VII) synergistic strategy, and a new reactivity pattern focused on reducing the reduction potential of the contaminant, as opposed to increasing the oxidation potential of oxidants.

Investigating the Mechanisms of Antibody Binding to Alpha-Synuclein for the Treatment of Parkinson's Disease.

Parkinson's disease (PD) is an idiopathic neurodegenerative disorder with the second-highest prevalence rate behind Alzheimer's disease. The pathophysiological hallmarks of PD are both degeneration of dopaminergic neurons in the substantia nigra pars compacta and the inclusion of misfolded α-synuclein (α-syn) aggregates known as Lewy bodies. Despite decades of research for potential PD treatments, none have been developed, and developing new therapeutic agents is a time-consuming and expensive process. Computational methods can be used to investigate the properties of drug candidates currently undergoing clinical trials to determine their theoretical efficiency at targeting α-syn. Monoclonal antibodies (mAbs) are biological drugs with high specificity, and Prasinezumab (PRX002) is an mAb currently in Phase II, which targets the C-terminus (AA 118-126) of α-syn. We utilized BioLuminate and PyMol for the structure prediction and preparation of the fragment antigen-binding (Fab) region of PRX002 and 34 different conformations of α-syn. Protein-protein docking simulations were performed using PIPER, and 3 of the docking poses were selected based on the best fit. Molecular dynamics simulations were conducted on the docked protein structures in triplicate for 1000 ns, and hydrogen bonds and electrostatic and hydrophobic interactions were analyzed using MDAnalysis to determine which residues were interacting and how often. Hydrogen bonds were shown to form frequently between the HCDR2 region of PRX002 and α-syn. Free energy was calculated to determine the binding affinity. The predicted binding affinity shows a strong antibody-antigen attraction between PRX002 and α-syn. RMSD was calculated to determine the conformational change of these regions throughout the simulation. The mAb's developability was determined using computational screening methods. Our results demonstrate the efficiency and developability of this therapeutic agent.

Photoinduced anisotropy in thin films of azobenzene-containing liquid crystalline supramolecular complexes of various polymer architecture.

Light patternable colorless liquid crystalline (LC) polymers are promising materials for functional photonic devices with broad applications in optical communication, diffractive optics, and displays. This work reports photoinduced optical anisotropy in thin films of azobenzene-containing (Azo) LC block copolymer supramolecular complexes, which can be decolorized after light patterning providing colorless patterned birefringent polymer films. The supramolecular complexes are prepared via intermolecular pyridine-phenol hydrogen bonding between a low-molecular-weight Azo phenol and host LC AB diblock and ABA triblock copolymers consisted of LC phenylbenzoate (PhM) blocks and poly(vinylpyridine) units. The molecular architecture of the host polymers and the morphological pattern formed by the complexes can affect orientational behavior of Azo groups under irradiation with linearly polarized light. Photoorientation of hydrogen-bonded Azo groups is accompanied by the cooperative orientation of non-photochromic PhM units, which form individual microphases and stabilize the orientation of Azo groups. This effect is specific for block copolymer complexes and it is absent for random copolymer complex, which is used as a reference sample. Optical anisotropy induced in films of the block copolymer complexes can be amplified by heating above the glass transition temperature and subsequent rinsing with diethyl ether allows colorless birefringent polymer films to be prepared.

How Flexible Is the Hydrogen Sulfide Molecule Structure? Influence of Hydrogen Sulfide Molecule Geometry on Its Hydrogen Bonds.

The geometry of hydrogen sulfide was studied by calculating potential energy surface (PES) with over  1800 configurations. The calculations were performed at very accurate  CCSD(T)/aug-cc-pvz5 level. The most stable geometry on PES has bond angle (H-S-H) of 92.40° and bond length (S-H) of 1.338 Å. PES shows that hydrogen sulfide is a quite flexible molecule. Namely, it can change the bonding angle (H-S-H) in the range of . 15.6° (from 84.6° to 100.2°) and the bond lengths (S-H) in the range of 0.082 Å (from 1.299 Å to 1.381 Å) with an energy increase of only 1.0 kcal/mol. An influence of hydrogen sulfide geometry on its hydrogen bonds was studied on several hydrogen sulfide/hydrogen sulfide and water/hydrogen sulfide dimers. It showed that the change of hydrogen sulfide geometry does not influence the strength of hydrogen bond. Fully optimized geometries in gas and water solution phases revealed structural differences of both monomers and dimers in gas phase and water phase. SAPT analysis of the optimized dimer geometries showed that in all the dimers electrostatic is the most dominant contribution, while, in the dimers with hydrogen sulfide, the influence of dispersion contribution becomes quite pronounced.

Integrated identification and detection of hydration state and its evolution using terahertz technology.

The accurate detection of dehydration processes in hydrated drugs can reveal various intermolecular vibration modes mediated by hydrogen bonds between water molecules and other components, which underpin the further development of pharmaceutical science, food safety and biophysics. Herein, terahertz (THz) technology is utilized to investigate the dehydration state of d(+)-Raffinose pentahydrate (Rf·5H2O), in conjunction with imaging-based point by point scanning data acquisition and barcodes methods, to establish an innovative platform integrated identification, trace detection, and application capabilities. Our study demonstrates that the dehydration process of Rf·5H2O can be dynamically monitored through the evolution of its THz absorption peaks, offering more precise results compared to XRD and Raman spectroscopies. Moreover, the absorbance spectra data collected at each individual pixel is utilized to build visualized THz images, achieving an ultralow minimum content required for detection of 0.032 µg/(50 µm)2. Additionally, we introduce a THz spectra-barcode conversion system that not only ensures efficient electronic recordkeeping but also enhances user readability, thereby facilitating the practical applications of THz technology.

Norfloxacinium nitrate.

In the title salt [systematic name: 4-(3-carb-oxy-1-ethyl-6-fluoro-4-oxo-1,4-di-hydro-quin-olin-7-yl)piperazin-1-ium nitrate], C16H19FN3O3 +·NO3 -, proton transfer from nitric acid to the N atom of the piperazine ring of norfloxacin has occurred to form a mol-ecular salt. In the extended structure, N-H⋯O hydrogen bonds link alternating cations and anions into [100] chains, which are reinforced by aromatic π-π stacking inter-actions between the quinoline moieties of the norfloxacinium cations.