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Nedergaard Vasquez posted an update 3 days, 8 hours ago
We report an intracellular imaging and assay nanoplatform for RNase A using a DNA tetrahedron-based fluorescent probe as a substrate. Importantly, a natural compound was used as an RNase A activity stimulator to improve the sensitivity. selleck chemicals This platform provides an alternative for the diagnosis and prognosis of RNase A-related diseases and drug screening.Cucurbituril analogues can bear some of the chemical and physical characteristics of their parental origin and are derived wholly or in part from glycolurils (including homologues). The development of analogues is discussed from their earliest origins to the most recent developments, which includes deviations in binding properties and the inclusion of alternative molecular units in conjunction with glycolurils. Examples of alternative guest binding are discussed and compared to the behaviour of conventional cucurbituril.We have accomplished the ruthenium-catalyzed benzylic substitution of benzyl esters with a stabilized carbon nucleophile. A [Cp*RuCl2]2/picolinic acid catalyst system promoted the reaction of 2-naphthylmethyl-2,3,4,5,6-pentafluorobenzoates with a series of stabilized carbon nucleophiles such as malonates, β-ketoesters, and diketones to give the corresponding benzylic alkylation products in moderate to high yields. We proposed a plausible reaction mechanism that could involve a (π-benzyl)ruthenium intermediate.Azo radical anion 1˙- and dianion 12- have been isolated by one- and two-electron reduction of the azo compound 1 (ArNNAr, Ar = 4-CN-2,6-iPr2-C6H2) with alkali metals, respectively. The reduced species have been characterized by single-crystal X-ray analysis, EPR, UV and FT-IR spectroscopy, as well as SQUID measurements. The filling of one and two electrons in the π* orbital of the N-N double bond of 1 leads to a half-double N-N bond in 1˙- and a single N-N bond in 12-. The uncoordinated nature of these reduced species enables them to activate CO2. The exposure of 1˙- solution to CO2 led to the formation of oxalate anion C2O42-, while that of 12- solution to CO2 afforded the hydrazine dicarboxylate dianion [1-2CO2]2-, which reversibly dissociated back to 1 and CO2 upon oxidation.Structurally elusive inositol hexakisphosphates have been trapped in host-guest sandwiches between two picolinamide macrocycles that remain intact in solution, aided by hydrogen bonds and electrostatic interactions. This first report of macrocyclic complexes of inositol hexakisphosphates provides structural insight to significant biosources of phosphorus that impact the global phosphorus cycle.An approach to rationally design optimal alloy catalysts is established using nitric oxide (NO) oxidation as an example. We introduce a quantitative structure-energy equation to predict the chemisorption energies of adsorbates on alloy catalysts. The structure-energy descriptor is used to rationally design Pt-based and Ni-based alloy catalysts for NO oxidation. Full first principles calculations with kinetic simulations demonstrate that these designed catalysts possess much better catalytic performances than the traditional catalysts.A new iodide layered double perovskite (C3H9NI)4AgBiI8 (IPAB) has been developed based on a short-chain spacer cation, which is the first homologous compound in iodide double perovskites that adopt the Ruddlesden-Popper structure type. Importantly, IPAB is a promising environmentally friendly alternative to the recently rapidly progressing lead halide semiconductors owing to its narrow direct-bandgap of 1.87 eV and excellent stability.For the first time, we report an interesting transition from conventional core-shell polymer/SiO2 particles to self-stable snowman-like particles, which can be achieved by adding a low-boiling point oil-soluble monomer because the volatile monomer not only plays a lubrication role, but also acts as a gas “motor” to drive the silica precursor polycondensate migration.A well-defined crystalline cyano-functionalized graphdiyne (CN-GDY) is synthesized at a liquid/liquid interface through alkyne-alkyne coupling reactions. The configurations and nanostructures of CN-GDY were well characterized by TEM, SEM, AFM, XPS, and Raman spectroscopy. HR-TEM and selected area electron diffraction (SAED) in combination with structure simulation firmly revealed a 9-fold stacking mode for CN-GDY.Near-infrared fluorescence imaging in the 1000-1700 nm-wavelength window (NIR-II) has exhibited great potential for deep-tissue bioimaging due to its diminished auto-fluorescence, suppressed photo-scattering, deep penetration, and high spatial and temporal resolutions. Various kinds of inorganic nanomaterials have been extensively developed for NIR-IIa (1300-1400 nm) and NIR-IIb (1500-1700 nm) bioimaging. However, the development of small-molecule NIR-IIa and NIR-IIb fluorophores is still in its infancy. Herein, we designed and synthesized a novel NIR-II organic aggregation-induced emission (AIE) fluorophore (HQL2) with a fluorescence tail extending into the NIR-IIa and NIR-IIb region based on our previous reported skeleton Q4. The encapsulated NIR-II AIE nanoparticles (HQL2 dots) exhibited water solubility and biocompatibility, and high brightness for NIR-IIa and NIR-IIb vascular imaging in vivo, a first for NIR-II AIE dots.Controlled polymerization through living radical polymerization is widely studied. Controlled polymerization enables synthetic polymers with precise structures, which have the potential for excellent bio-functional materials. This review summarizes the applications of controlled polymers, especially those via living radical polymerization, to biofunctional materials and conjugation with biomolecules. In the case of polymer ligands like glycopolymers, the polymers control the interactions with proteins and cells based on the precise polymer structures. Living radical polymerization enables the conjugation of polymers to proteins, antibodies, nucleic acids and cells. Those polymer conjugations are a sophisticated method to modify bio-organisms. The polymer conjugations expand the potential of biofunctional materials and are useful for understanding biology.