Imaging of hypoxia in vivo helps with accurate cancer diagnosis and evaluation of therapeutic outcomes. Here we report a Pt(II) metallacage with oxygen‐responsive red phosphorescence and steady fluorescence for in vivo hypoxia imaging and chemotherapy. Intriguingly, the therapeutic agent and diagnostic probe are sophisticatedly integrated into the metallacage through heteroligation‐directed self‐assembly. Nanoformulation by encapsulating the metallacage into nanoparticles greatly enhance its...
Sat Jul 25, 2020 17:43
We report chemically fuelled out‐of‐equilibrium self‐replicating vesicles based on surfactant formation. We studied the vesicles’ autocatalytic formation using UPLC to determine monomer concentration and interferometric scattering microscopy at the nanoparticle level. Unlike related reports of chemically fuelled self‐replicating micelles, our vesicular system was too stable to surfactant degredation to be maintained out of equilibrium. The introduction of a catalyst, which introduces a second catalytic...
Fri Jul 24, 2020 22:00
Herein, norbornyl (NB), a bulky annular nonconjugated (CN‐type) spacer, is melded into π systems to construct two groups of ladder‐type room‐temperature phosphorescence (RTP) luminogens. The effect of the CN‐type moiety on π−π interactions, packing modes and RTP performance is explored systematically. The experimental and computational results demonstrate the versatility of NB in reducing π−π distances and synergistically intensifying the intermolecular interactions, which not only induces intersystem...
Fri Jul 24, 2020 21:14
The utilization of N‐centered radicals to synthesize nitrogen‐containing compounds has attracted considerable attention recently, due to their powerful reactivities and the concomitant construction of C−N bonds. However, the generation and control of N‐centered radicals remain particularly challenging. Herein we report a tethering strategy using SOMO‐HOMO converted distonic radical anions for the site‐specific aminations of imidates and amidines with aid of the non‐covalent interaction, which features...
Fri Jul 24, 2020 19:19
We report the reconfigurable assembly of rod‐shaped eutectic gallium‐indium alloy (EGaIn) liquid metal colloidal motors by mimicking the dandelion flower’s growing process. The EGaIn nanorod with a diameter of 210 nm and a length of 850 nm was synthesized via an ultrasound‐assisted physical dispersion and demonstrated to be a core‐shell structure with a 30 nm GaOOH shell and zero‐valent liquid core. The EGaIn motors could autonomously move at a speed of 41.2 μm/s under an acoustic field. By modulating...
Fri Jul 24, 2020 19:18
Gallium(III)‐based drugs have gained momentum in cancer therapy for the relevance to iron‐dependent anticancer activity. Judicious choice of ligands is critical to design Ga(III) drugs with improved oral bioavailability, antitumor efficacy and even the distinct mechanism from simple Ga(III) salts. Herein, we first describe Ga(III) complexes of planar tetradentate salen ligands (salen=2,3‐bis[(4‐dialkylamino‐2‐hydroxybenzylidene)amino] but‐2‐enedinitrile)) as well as labile axial solvent ligands,...
Fri Jul 24, 2020 18:18
Polyethylene terephthalate (PET) is selectively depolymer‐ized by a carbon‐supported single‐site molybdenum‐dioxo catalyst to terephthalic acid (PTA), and ethylene. The solventless reactions are most efficient under 1 atmosphere of H 2 . The catalyst exhibits high stability and can be recycled multiple times without loss of activity. Waste beverage bottle PET or a PET + polypropylene (PP) mixture (simulating the bottle + cap) proceeds at 260°C with complete PET deconstruction and quantitative PTA...
Fri Jul 24, 2020 16:50
Oxidative anion insertion into graphite in an aqueous environment represents a significant challenge to construct aqueous dual‐ion batteries. In dilute aqueous electrolytes, oxygen evolution reaction dominates the anodic current before anions can be inserted into the graphite gallery. Here, we report that the reversible insertion of Mg‐Cl superhalides in graphite delivers a record‐high reversible capacity of 150 mAh g ‐1 from an aqueous deep eutectic solvent comprising magnesium chloride and choline...
Fri Jul 24, 2020 16:49
The generation of highly organized amyloid fibrils is associated with a wide range of conformational pathologies, including primarily neurodegenerative diseases. Such disorders are characterized by misfolded proteins (amyloids) that lose their normal physiological roles and acquire toxicity. Recent findings suggest that the accumulation and spread of amyloids arises from proteostasis network impairment. These observations are certainly contributing to the current change of focus in anti‐amyloid...
Fri Jul 24, 2020 16:43
We report a robust method for effectively removing the chemisorbed Br− ions, a capping agent, from the surface of Pd nanocubes to maximize their catalytic activity. The Br− ions can be removed by simply heating the sample in water, but the desorption of Br− ions will expose the underneath Pd atoms to the O2 from air for the formation of a relatively thick oxide layer. During potential cycling, the oxide layer evolves into detrimental features such as steps and terraces. By introducing a trace amount...
Fri Jul 24, 2020 15:14
Water is the most important and universal substance in nature. People have been striving to pursue and discover water‐related processes and imitate these important discoveries for the benefit of mankind. As a successful example of human imitating the formation of natural materials, molecular sieves have been synthesized under hydrothermal condition and applied in industry. Herein, we reveal an unforeseen observation on a very special water‐induced structural dynamic process of these materials. Dynamic...
Fri Jul 24, 2020 13:44
Authority zero : Process monitoring of a hydrogenation reaction using zero‐field NMR spectroscopy is possible if the reaction is performed with H2 gas enriched in the para nuclear spin isomer, which gives hyperpolarized NMR signals. Zero‐field NMR allows the reaction to be monitored through a metal tube during continuous bubbling of hydrogen into solution, while maintaining the specificity of high‐field NMR spectroscopy. Abstract We demonstrate that heterogeneous/biphasic chemical reactions...
Fri Jul 24, 2020 13:33
The electroreduction of carbon dioxide using renewable electricity is an appealing strategy for the sustainable synthesis of chemicals and fuels. Extensive research has focused on the production of ethylene, ethanol and n ‐propanol, but more complex C 4 molecules have been scarcely reported. Herein, we report the first direct electroreduction of CO 2 to 1‐butanol in alkaline electrolyte on Cu gas diffusion electrodes (Faradaic efficiency = 0.056%, j 1‐butanol = −0.080 mA cm −2 at −0.48...
Fri Jul 24, 2020 13:15
Twist and modify ! Enzymatic and structural investigation of the lipolanthine biosynthesis revealed the leader peptide of microvionin to form an amphipathic α‐helix, containing a highly conserved, hydrophobic (θxx)θxxθxxθ motif essential for enzymatic modification and subsequent proteolytic degradation. Efficient processing is additionally dependent on mutual regulation between the corresponding maturation enzymes. Abstract The recently discovered strongly anti‐Gram‐positive lipolanthines...
Fri Jul 24, 2020 12:19
Hydride abstraction from the heterocyclic carbene borane adducts (NHC)BH2C6F5 (NHC: IMes or IMe4) gives the B–H containing [(NHC)B(H)C6F5]+ borenium cations. They add carbon monoxide to give the respective [(NHC)B(H)(C6F5)CO]+ boron carbonyl cations. Carbon nucleophiles add to the boron carbonyl to give [B](H) acyls. Hydride reduces the [B]CO cation to hydroxymethylborane derivatives.
Thu Jul 23, 2020 21:45
Diabetes mellitus is a lifelong metabolic disease that requires frequent subcutaneous injections of insulin. However, this method of administration can be associated with patient discomfort and local tissue infection. Oral delivery of insulin has been pursued as a more convenient method for diabetes treatment, given its likely superior patient compliance and convenience as well as cost‐effectiveness. However, various biological barriers hinder the clinical translation of oral insulin. The rapid development...
Thu Jul 23, 2020 21:44
Caught in the Hinact : [FeFe] hydrogenases are highly efficient catalysts for the interconversion of H2 and H+. However, they are highly O2 sensitive. Here, the X‐ray crystal structure of an O2‐stable state of [FeFe] hydrogenase, along with comprehensive spectroscopic analysis and molecular calculations reveals the presence of a sulfur ligand bound to the active site. These results provide crucial insight into O2 stability mechanisms in proteins. Abstract [FeFe] hydrogenases are the most...
Thu Jul 23, 2020 20:55
Let's assemble them all ! Using either coordination chemistry or organometallic approaches, diverse metallo‐multihelicenic systems can be designed. The association of helically chiral π‐conjugated ligands in close proximity with metal centers results in sophisticated architectures exhibiting new properties compared with the corresponding monohelicenic structures. Abstract The preparation of multihelicenic systems by conventional organic synthesis is a challenging task and under continuous...
Thu Jul 23, 2020 20:48
Make it shine : We report a photocatalyzed ring‐opening fluorination of cyclopropylamides and cyclobutylamides. Both cheap benzophenone with UVA light or organic and inorganic dyes with blue light could be used to promote this process. Various fluorinated amines were obtained through nucleophilic attack on the formed hemiaminals in one pot, giving access to a broad range of useful building blocks for medicinal chemistry. Abstract We report an oxidative ring‐opening strategy to transform...
Thu Jul 23, 2020 20:47
Taming superoxide : Two dual‐acting compounds (SOPD‐NAC and SOPD‐Pep ) that scavenge superoxide and then decompose to release persulfides (RSSH) are reported. Both donors deliver persulfides to cardiomyocytes, lowering intracellular reactive oxygen species levels. Additionally, SOPD‐Pep shows anti‐inflammatory activity in macrophages, greater than SOPD‐NAC and several H2S‐releasing control compounds. Abstract Overproduction of superoxide anion (O2 .−), the primary cellular reactive...
Thu Jul 23, 2020 20:46
Direct depletion of lactate accumulated in the tumor microenvironment holds promise for cancer therapy, but remains challenging. Here we report a one‐pot synthesis of openwork@ dendritic mesoporous silica nanoparticles (ODMSN) to address this problem. ODMSN self‐assembled through a time‐resolved lamellar growth mechanism feature an openworked core and a dendritic shell, both constructed by silica nanosheets of ~3 nm. With a large pore size, high surface area and pore volume, ODMSN exhibited a high...
Thu Jul 23, 2020 20:19
Salivary elimination is an important pathway for the body to excrete small molecules and digestive enzymes. However, it has never been considered in the elimination of engineered nanoparticles. Herein, we reported an interesting finding that renal clearable near‐infrared emitting glutathione coated silver nanoparticles of ~2nm (GS‐AgNPs) can selectively accumulate in the submandibular salivary gland, followed by being excreted in its excretory duct. By conducting a head‐to‐head comparison on...
Thu Jul 23, 2020 19:21
Co‐based spinel oxides are considered as promising catalysts for the electrochemical oxidation of 5‐hydroxymethylfurfural (HMF) to high‐value chemicals. Co 3 O 4 is of mixed valences with the presence of both Co 2+ and Co 3+ at different atom locations. Identifying the activity of each atomic site is critical to propose the design principle of advanced electrocatalysts, and tuning the geometrical sites at the atom level in Co 3 O 4 could lead to significant modifications on its electronic...
Thu Jul 23, 2020 18:14
A promising route to the synthesis of protein‐mimetic materials that are capable of strong mechanics and complex functions is provided by intermolecular β‐sheet stacking. An understanding of the assembly mechanism on β‐sheet stacking at molecular‐level and the related influencing factors determine the potential to design polymorphs of such biomacromolecular materials towards broad applications. Herein, we quantitatively reveal the air/water interface (AWI) parameters regulating the transformation...
Thu Jul 23, 2020 16:45
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