Molecular Programming Design of Glyconucleic Acid Aptamer with High Stability.

Functional nucleic acids (FNAs), possessing specific biological functions beyond their informational roles, have gained widespread attention in disease therapeutics. However, their clinical application is severely limited by their low serum stability in complex physiological environments. In this work, a precise molecular programming strategy is explored to prepare glyconucleic acid aptamers (GNAAs) with high serum stability.

Oligonucleotide Containing 8-Trifluoromethyl-2'-Deoxyguanosine as a Z-DNA Probe.

Z-DNA structure is a noncanonical left-handed alternative form of DNA, which has been suggested to be biologically important and is related to several genetic diseases and cancer. Therefore, investigation of Z-DNA structure associated with biological events is of great importance to understanding the functions of these molecules. Here, we described the development of a trifluoromethyl labeled deoxyguanosine derivative and employed it as a F NMR probe to study Z-form DNA structure in vitro and in living cells.

Composite capillary carbon tube NbWOas advanced anode material for aqueous ion capacitors.

Niobium-tungsten bimetal oxides have received wide attention due to their excellent lattice properties. In this work, NbWO(NbWO) with a tetragonal tungsten bronze structure was synthesized by simple hydrothermal method. NbWO was modified to provide high specific surface area via combining with hollow carbon nanotubes.

Study on nanocellulose isolated from waste chilli stems processing as dietary fiber in biscuits.

In order to expand the high added value of waste chilli stems and the recycling of green resources, cellulose in chilli stems was extracted by nitric acid-ethanol method, and nanocellulose was prepared by sulfuric acid hydrolysis method. The results showed that the cellulose content was between 15% and 34.5%.

A Unique Fe-N Coordination System Enabling Transformation of Oxygen into Superoxide for Photocatalytic CH Activation with High Efficiency and Selectivity.

Selective oxidation of CH bonds is one of the most important reactions in organic synthesis. However, activation of the α-CH bond of ethylbenzene by use of photocatalysis-generated superoxide anions (O ) remains a challenge. Herein, the formation of individual Fe atoms on polymeric carbon nitride (CN), that activates O  to create O for facilitating the reaction of ethylbenzene to form acetophenone, is demonstrated.

A cationic thorium-organic framework with triple single-crystal-to-single-crystal transformation peculiarities for ultrasensitive anion recognition.

Single-crystal-to-single-crystal transformation of metal-organic frameworks has been met with great interest, as it allows for the creation of new materials in a stepwise manner and direct visualization of structural transitions when subjected to external stimuli. However, it remains a peculiarity among numerous metal-organic frameworks, particularly for the ones constructed from tetravalent metal cations. Herein, we present a cationic thorium-organic framework displaying unprecedented triple single-crystal-to-single-crystal transformations in organic solvents, water, and NaIO solution.

UiO-66-NH-(AO) MOFs with a New Ligand BDC-NH-(CN) for Efficient Extraction of Uranium from Seawater.

Metal-organic frameworks (MOFs) with a high surface area and excellent stability are potential candidates for uranium (U) adsorption. Amidoxime (AO) is the most widely used functional group to extract U, which is usually introduced into MOFs by two-step post-synthetic methods (PSMs). Herein, MOF UiO-66-NH-(AO) was obtained by a one-step PSM with amidoximation from UiO-66-NH-(CN), which was synthesized by a new organic ligand of 2-cyano-terephthalic acid and whose morphology was octahedron and could be well controlled with the new ligand.

Selective Capture Mechanism of Radioactive Thorium from Highly Acidic Solution by a Layered Metal Sulfide.

Thorium as a potential nuclear fuel for the next-generation thorium-based molten salt reactors holds significant environmental and economic promise over the current uranium-based nuclear reactors. However, because thorium (Th) usually coexists with other rare earth elements, alkali or alkaline earth metals in minerals, or highly acidic radioactive waste, seeking acid-resistant sorbents with excellent selectivity, high capacity, and fast removal rate for Th is still a challenging task. In this work, we investigated a robust layered metal sulfide (KInSnS, KMS-5) for Th removal from strong acidic solutions.

Efficiently immobilizing uranium (VI) by oxidized carbon foam.

Oxidized carbon foam (oxidized CF) was prepared by using a facile chemical oxidation treatment at relatively low temperature of 450 °C and applied to capture uranyl cation [U(VI)] from aqueous solutions. The effects of pH, contact time, initial U(VI) concentration, and temperature on the U(VI) absorption performance of oxidized CF were investigated by batch experiments. The oxidized CF was illustrated to exhibit fast sorption kinetics (92% removal within 15 min and 98% removal in 2 h) and high sorption capacity (305.

Metal-organic frameworks loaded on phosphorus-doped tubular carbon nitride for enhanced photocatalytic hydrogen production and amine oxidation.

It is still a challenge to evolve visible light photocatalysts that possess both efficient oxidation and reduction capabilities. In this paper, phosphorus-doped tubular carbon nitride@UiO-66-NH (p-TCN@U6-X) composites were prepared by in-situ load of UiO-66-NH on the surface of p-TCN based on solvothermal method, which exhibit excellent photocatalytic oxidation and reduction ability. As a result, under visible light irradiation (λ > 420 nm), the photocatalytic H production performance of p-TCN@U6-3 reached 2628 μmol gh, which was 8.

Observation of Z-DNA Structure via the Synthesis of Oligonucleotide DNA Containing 8-Trifluoromethyl-2-Deoxyguanosine.

This article contains detailed synthetic protocols for the preparation of DNA oligonucleotides containing 8-trifluoromethyl-2'-deoxyguanosine ( dG) and their application to observe Z-DNA structure in vitro and in living HeLa cells. First, using a catalytic system consisting of FeSO , H SO , and H O in DMSO, we achieved a one-step synthesis of dG through a radical reaction between deoxyguanosine (dG) and CF I, with a yield of 45%. We then obtained the 3'-phosphoramidite of dG through a routine three-step procedure.

Achieving UV and X-ray Dual Photochromism in a Metal-Organic Hybrid via Structural Modulation.

Rational design and synthesis of new photochromic sensors have been active research areas of inquiry, particularly on how to predict and tailor their properties and functionalities. Herein, two thulium 2,2':6',2''-terpyridine-4'-carboxylate (TPC)-functionalized metal-organic hybrids, Tm(TPC)(HCOO)(HO) () and Tm(TPC)(HCOO) () with different photochromic response behaviors, have been successfully prepared, allowing for straightforward investigations of the structure-property correlation. Single-crystal X-ray diffraction and electron paramagnetic resonance analyses revealed that the incorporation of a unique dangling decorating TPC unit in offers a shorter and more accessible π-π interaction pathway between the adjacent TPC moieties than that in .

Tuning of the Network Dimensionality and Photoluminescent Properties in Homo- and Heteroleptic Lanthanide Coordination Polymers.

Targeted synthesis, through a heteroleptic methodology, has resulted in three types of lanthanide (Ln) coordination polymers (CPs) with tailored dimensionality, tunable photoluminescent colors, and distinct luminescence quenching upon UV and X-ray irradiation. The homoleptic Ln(tpbz)(NO) [; tpbz = 4-(2,2':6',2″-terpyridin-4'-yl)benzoate] is assembled from Ln cations and bridging tpbz ligands, accompanied by the decoration of NO anions, forming a one-dimensional (1D) chain structure. The presence of ancillary dicarboxylate linkers, 1,4-benzenedicarboxylate (bdc) and 2,5-thiophenedicarboxylate (tdc), promotes additional bridging between 1D chains to form a two-dimensional layer and a three-dimensional framework for Ln(tpbz)(bdc) () and Ln(tpbz)(tdc) (), respectively.

Improving Thermodynamic Stability and Anticoagulant Activity of a Thrombin Binding Aptamer by Incorporation of 8-trifluoromethyl-2'-deoxyguanosine.

In this study, we incorporated 8-trifluoromethyl-2'-deoxyguanosine (G) into a thrombin binding aptamer (TBA). Circular dichroism, nuclear magnetic resonance (NMR), electrophoresis, and prothrombin time (PT) assay were performed to investigate the structure, thermodynamic stability, biological stability, and anticoagulant activity of the G-modified TBA sequences. We found that the replacement of G into TBA sequences led to a remarkable improvement in the melting temperature up to 30 °C compared with the native sequence.

Linear consecutive hexaoxazoles as G4 ligands inducing chair-type anti-parallel topology of a telomeric G-quadruplex.

G-quadruplex structures (G4s) in guanine-rich regions of DNA play critical roles in various biological phenomena, including replication, translation, and gene expression. There are three types of G4 topology, , parallel, anti-parallel, and hybrid, and ligands that selectively interact with or stabilize a specific topology have been extensively explored to enable studies of topology-related functions. Here, we describe the synthesis of a new series of G4 ligands based on 6LCOs (6-linear consecutive oxazoles), , L2H2-2M2EA-6LCO (2), L2A2-2M2EAc-6LCO (3), and L2G2-2M2EG-6LCO (4), which bear four aminoalkyl, acetamidealkyl, and guanidinylalkyl side chains, respectively.

Structural Complexity and Magnetic Orderings in a Large Family of 3d-4f Heterobimetallic Sulfates.

The synthesis of a large family of heterobimetallic lanthanide copper sulfates was realized via stoichiometric hydrothermal reactions among LnO, CuO, and HSO, giving rise to four distinct phases, namely LnCu(SO)(OH) (Ln = Sm-Ho) (), LnCu(SO)(OH) (Ln = Tm-Lu) (), LnCu(SO)(OH) (Ln = Nd-Gd, except Pm) (), and LnCu(SO)(OH) (Ln = Dy-Lu) (), with completely different topologies. The passage from and to and across the 4f series, respectively, can be ascribed to the effect of lanthanide contraction, which progressively induces shrinking of the Ln-O distance, reduction in the Ln coordination number, and eventually structural transitions. The incorporation of identical 3d-4f metal ions into different spin-lattices, in conjunction with substitution of diverse Ln cations within the same spin-lattice, gives rise to tunable magnetic properties varying from ferromagnetic ordering in and to antiferromagnetic ordering in , and to paramagnetic correlations found in and .

Oligonucleotides DNA containing 8-trifluoromethyl-2'-deoxyguanosine for observing Z-DNA structure.

Z-DNA is known to be a left-handed alternative form of DNA and has important biological roles as well as being related to cancer and other genetic diseases. It is therefore important to investigate Z-DNA structure and related biological events in living cells. However, the development of molecular probes for the observation of Z-DNA structures inside living cells has not yet been realized.

A Promoted Charge Separation/Transfer System from Cu Single Atoms and C N Layers for Efficient Photocatalysis.

Establishing highly effective charge transfer channels in carbon nitride (C N ) for enhancing its photocatalytic activity is still a challenging issue. Herein, for the first time, the engineering of C N layers with single-atom Cu bonded with compositional N (CuN ) is demonstrated to address this challenge. The CuN is formed by intercalation of chlorophyll sodium copper salt into a melamine-based supramolecular precursor followed by controlled pyrolysis.

Telomeric DNA-RNA-hybrid G-quadruplex exists in environmental conditions of HeLa cells.

In the present study, we employed a F NMR approach to study the association of telomere RNA and DNA in vitro and in living human cells. We successfully characterized the DNA-RNA hybrid G-quadruplex (HQ) structure formed by telomeric DNA and RNA. We further demonstrated for the first time that an HQ conformation can exist in the environmental conditions of HeLa cells.

The physical chemistry of uranium (VI) immobilization on manganese oxides.

Manganese oxides show strong affinity towards uranium, and have a promising application in uranium immobilization in environmental protection. We successfully synthesized a series of Mn oxide materials of different structures and investigated their U(VI) immobilization performances. The results showed that all Mn oxides share similar sorption capacities per unit surface area, implying similar physical chemistry during immobilization.

Investigation of the local structure of molten ThF-LiF and ThF-LiF-BeF mixtures by high-temperature X-ray absorption spectroscopy and molecular-dynamics simulation.

The microscopic structures of ThF-LiF and ThF-LiF-BeF molten salts have been systematically investigated by in situ high-temperature X-ray absorption fine-structure (XAFS) spectroscopy combined with molecular-dynamics (MD) simulations. The results reveal that the local structure of thorium ions was much more disordered in the molten state of the ThF-LiF-BeF salt than that in ThF-LiF, implying that the Th and F ions were exchanged more frequently in the presence of Be ions. The structures of medium-range-ordered coordination shells (such as Th-F and Th-Th) have been emphasized by experimental and theoretical XAFS analysis, and they play a significant role in transport properties.

F NMR Spectroscopy for the Analysis of DNA G-Quadruplex Structures Using F-Labeled Nucleobase.

G-quadruplex structures have been suggested to be biologically important in processes such as transcription and translation, gene expression and regulation in human cancer cells, and regulation of telomere length. Investigation of G-quadruplex structures associated with biological events is therefore essential to understanding the functions of these molecules. We developed the F-labeled nucleobases and introduced them into DNA sequences for the F NMR spectroscopy analysis.