Totally found 97 items.

  • [期刊] Crosstalk-free colloidosomes for high throughput single-molecule protein analysis
    Droplet microfluidics is a powerful platform for high-throughput single-molecule protein analysis. However, the issues of coalescence and crosstalk of droplets compromise the accuracy of detection and hinder its wide application. To address these limitations, a novel colloidosome-based method was presented by combining a Pickering emulsion with droplet microfluidics for single-molecule protein analysis. Utilizing the self-assembly of easily synthesized colloidal surfactant F-SiO_2 NPs at the water/oil interface, the colloidosomes are rigidly stabilized and can effectively avoid the leakage of fluorescent molecules. The crosstalk-free colloidosomes enable high-throughput single-molecule protein analysis, including heterogenous dynamic studies and digital detection. As a robust and accurate method, colloidosome-based microfluidics is promising as a powerful tool for a wide variety of applications, such as directed enzyme evolution, digital enzyme-linked immunosorbent assay(ELISA), and screening of antibiotics.
  • [期刊] Intermolecular electronic coupling of 9-methyl-9H-dibenzo[a,c]carbazole for strong emission in aggregated state by substituent effect
    Bright emission of organic luminogens at aggregated state has attracted increasing attention for their potential applications in opto-electronic devices and bio-/chemo-sensors. In this article, upon the introduction of different substituents(Br, Ph and TPh) to the large conjugated core of 9-methyl-9 H-dibenzo[a,c]carbazole(DBC) moiety, the resultant luminogens demonstrated PL quantum yields in solid state ranging from 4.81% to 47.39%. Through the systematic investigation of molecular packing,together with theory calculation, the strong intermolecular electronic coupling in the dimers is proved as the main factor to the bright emission in the solid state. The results afforded a new avenue to investigate the intrinsic relationship among the molecular structures, packing modes and emission properties.
  • [期刊] Combinatorial synthesis of redox-responsive cationic polypeptoids for intracellular protein delivery application
    Biologics play an essential role in treating various indications from cancers to the metabolic diseases, while the current development of new classes of intracellular-acting protein drugs is still hindered because of high molecular mass and overall hydrophilicity of proteins creating extremely poor permeability across cell membrane. Hence, there remains an unmet need to develop safe, potent approaches to augment intracellular protein delivery efficiency. Here, we described a facile multicomponent reaction system for generating a small library of redox-responsive cationic polypeptoids with high biocompatibility. The co-assembly of optimized polymer with protein leads to the formation of compacted nanocomplexes with smaller size and high encapsulation efficiency, thus improving cellular internalization via the macropinocytosis and/or caveolae-mediated endocytosis mainly. After endo-lysosomal escape, the nanocomplexes can be disassociated to efficiently release cargo proteins into the cytosol, owing to the intracellular glutathione(GSH)-triggered rapid cleavage of disulfide bonds in polymers backbone. As a result, we screened a promising platform reagent for efficient cytosolic protein delivery application.
  • [期刊] Soluble triarylamine functionalized symmetric viologen for all-solid-state electrochromic supercapacitors
    Electrochromic supercapacitors have drawn enormous attention due to their ability to monitor the charge and discharge processes through color changes of electroactive materials. However, there are few work on small organic molecules as active materials for all-solid-state electrochromic supercapacitors. Herein, we reported two novel multifunctional symmetric viologens(TPA-bpy and CZ-bpy), which showed different solvatochromic, electrochromic, electroluminochromic and energy storage behaviors despite their similar chemical structures. The different performances between these two viologens were attributed to the difference in the intramolecular charge transfer capability and the solubility in organic solvents. Devices containing TPA-bpy displayed faster response time and higher coloration efficiency due to the introduction of packing-disruptive and three-dimensional triarylamine groups. Moreover, devices containing TPA-bpy also showed energy storage characteristics with an obvious color change from purple to yellow. It showed a wide voltage window(2.0 V), long discharge time(230.3 s at 0.01 mA cm~(-2)), and excellent cycling stability with 90% capacitance retention after 6,000 cycles. The work provides a new and convenient strategy towards the development of novel electrochromic capacitive materials.
  • [期刊] Visible-light-induced regioselective cross-dehydrogenative coupling of 2-isothiocyanatonaphthalenes with amines using molecular oxygen
    An efficient and eco-friendly protocol for the construction of naphtho[2,1-d]thiazol-2-amines through visible-light photoredoxcatalyzed C(sp~2)–H/S–H cross-dehydrogenative coupling reactions between 2-isothiocyanatonaphthalenes and amines was established. In this reaction, the new C–N and C–S bonds are formed simultaneously in a single step. This new method provides a straightforward approach for constructing valuable sulfur-containing compounds.
  • [期刊] Reducing energy loss via tuning energy levels of polymer acceptors for efficient all-polymer solar cells
    The open-circuit voltage(V_(oc)) of all-polymer solar cells(all-PSCs) is typically lower than 0.9 V even for the most efficient ones.Large energy loss is the main reason for limiting V_(oc)and efficiency of all-PSCs. Herein, through materials design using electron deficient building blocks based on bithiophene imides, the lowest unoccupied molecular orbital(LUMO) energy levels of polymer acceptors can be effectively tuned, which resulted in a reduced energy loss induced by charge generation and recombination loss due to the suppressed charge-transfer(CT) state absorption. Despite a negligible driving force, all-PSC based on the polymer donor and acceptor combination with well-aligned energy levels exhibited efficient charge transfer and achieved an external quantum efficiency over 70% while maintaining a large V_(oc)of 1.02 V, leading to a 9.21% efficiency. Through various spectroscopy approaches, this work sheds light on the mechanism of energy loss in all-PSCs, which paves an avenue to achieving efficient all-PSCs with large V_(oc)and drives the further development of all-PSCs.
  • [期刊] Vicinal Na~+ as structure guardians of atomically dispersed Ru catalysts in hydrogenation reactions
    Owing to the distinctive structural and electronic properties, atomically dispersed metal catalysts have raised tremendous attentions in the last ten years [1,2]. Generally,isolated metal atoms or clusters that dispersed across oxide supports (e.g., Al_2O_3, TiO_2, CeO_2) are stabilized through the coordination with supported O atoms, forming electrondeficient metal cations (M~(δ+)-O) at interfaces [3]
  • [期刊] Promoting selective electroreduction of nitrates to ammonia over electron-deficient Co modulated by rectifying Schottky contacts
    Developing efficient electrocatalysts for selective nitrate contamination reduction into value-added ammonia is significant. Here,heterostructured Co/CoO nanosheet arrays(Co/CoO NSAs) exhibited excellent Faradaic efficiency(93.8%) and selectivity(91.2%) for nitrate electroreduction to ammonia, greatly outperforming Co NSAs.~(15)N isotope labeling experiments and ~1H nuclear magnetic resonance(NMR) quantitative testing methods confirmed the origin of the produced ammonia. Electrochemical in situ Fourier transform infrared(FTIR) spectroscopy, online differential electrochemical mass spectrometry(DEMS)data and density functional theory(DFT) results revealed that the superior performances arose from the electron deficiency of Co induced by the rectifying Schottky contact in the Co/CoO heterostructures. The electron transfer from Co to CoO at the interface could not only suppress the competitive hydrogen evolution reaction, but also increase energy barriers for by-products, thus leading to high Faradaic efficiency and selectivity of ammonia.
  • [期刊] Recent advances in asymmetric synthesis with CO_2
    Carbon dioxide(CO_2) is an important and appealing C1 building block in chemical synthesis due to its nontoxicity, abundance,availability and sustainability. Tremendous progress has been achieved in the chemical transformation of CO_2 into high valueadded organic chemicals. However, the asymmetric synthesis with CO_2 to form enantioenriched molecules, especially the catalytic process, has lagged far behind. The enantioselective incorporation of CO_2 into organic compounds is highly desirable,as the corresponding chiral products, such as carboxylic acids and amino acids, are common structural units in a vast array of natural products and biologically active compounds. Herein, we discuss recent progress toward the enantioselective incorporation of CO_2 into organic molecules, which mainly rely on three strategies: 1) kinetic resolution or desymmetrization of epoxides with CO_2 to form chiral cyclic carbonates and polycarbonates; 2) nucleophilic attack of O-or N-nucleophiles to CO_2 in tandem with asymmetric C–O bond formation to prepare chiral cyclic carbonates and carbamates; 3) direct enantioselective nucleophilic attack of organometallic reagents to CO_2 with asymmetric C–C bond formation. Finally, challenges and future outlook in this area are also presented.
  • [期刊] Overall water splitting over conjugated polymer photocatalysts with crystal facets modulated
    Photocatalytic overall water splitting(OWS) for H2 and O2 evolution with a 2:1 stoichiometric ratio is one of the most promising ways to convert solar energy into chemical one,but it confronts huge challenges in consideration of the uphill water oxidation with four-electron transfer [1].