The interaction of water with small alcohols can be used as a model for understanding hydrophobic solvation of larger and more complex amphiphilic molecules. Despite its apparent simplicity, water/ethanol mixtures show important anomalies in several of their properties, like specific heat or partial molar volume, whose precise origin are still a matter of debate. Here we report high-resolution thermal conductivity, compressibility, and IR-spectroscopy data for water/ethanol solutions showing three distinct regions of solvation, related to changes in the H-bond network. Notably, the thermal conductivity shows a surprising increase of ≈3.1% with respect to pure water at dilute concentrations of ethanol (x = 0.025), which suggests a strengthening of H-bond network of water. Our results prove that the rate of energy transfer in water can be increased by hydrophobic solvation, due to the cooperative nature of the H-bond network.Designing efficient and low-cost electrocatalysts for the hydrogen evolution reaction (HER) is of great importance to advance water splitting technology towards practical applications. Herein, we report the preparation of IrCo nanoparticles supported on nitrogen-doped carbon (IrCo/NC) as a HER electrocatalyst in acidic and alkaline electrolytes. The IrCo/NC composite is obtained by pyrolyzing an Ir-doped Co(OH)2 precursor on g-C3N4, and is endowed with N-doped carbon and uniform IrCo alloy nanoparticles via a crystal confinement resulting from the Ir-doping into the Co(OH)2 layer. Electrocatalytic analysis shows that the IrCo/NC electrode requires low overpotentials of 32 mV at 10 mA cm-2 in 0.5 M H2SO4 and 33 mV in 1 M KOH, which are superior to those of the Co/NC and IrCo alloys that are free of Ir-doping or N-doped carbon. The results provide a strategy for designing and preparing active noble-transition bimetallic alloy electrocatalysts as efficient HER catalysts.The development of anode materials is critical to the success of sodium ion batteries (SIBs). Because of the size difference between Li and Na, the commercial anode material graphite in Li-ion batteries does not work for Na-ion batteries. Thus, it will be ideal if some universal anode materials could work for both Li- and Na-ion batteries with high performance. Inspired by a recent study on the high performance of a 2D-Si2BN sheet as an anode material for Li-ion batteries, we design a three dimensional (3D) porous structure by using the nanoribbons of a Si2BN sheet as building blocks. Based on the state-of-the-art ab initio calculations, we find that the resulting 3D porous Si2BN structure is stable chemically, dynamically and thermally, exhibiting a high specific capacity of 512.42 (341.61 mA h g-1), a low voltage of 0.27 V (0.15 V), a small volume expansion of 2.5% (2.7%), and a low migration energy barrier of 0.44 eV (0.19 eV) for Li- (Na-) ion batteries. These intriguing features, together with the light mass and rich abundance of Si, B and N, suggest that the 3D porous Si2BN structure is a promising candidate for the anode material of both Li- and Na-ion batteries.This report describes the synthesis of organoselenyl isoquinolinium imides through a tandem cyclization between N'-(2-alkynylbenzylidene)hydrazides and diselenides. The reaction was carried out at room temperature under an ambient atmosphere using cheap iron(iii) chloride as the metallic source. The strategy shows good tolerance to a broad range of N'-(2-alkynylbenzylidene)hydrazides and diselenides, and forms C-N and C-Se bonds in one step. The obtained product is further transformed into a bioactive H-pyrazolo[5,1-a]isoquinoline skeleton easily via a silver catalyzed [3 + 2] cycloaddition.Self-assembled nanostructures arise when building blocks spontaneously organize into ordered aggregates that exhibit different properties compared to the disorganized monomers. Here, we study an amphiphilic cyanine dye (C8S3) that is known to self-assemble into double-walled, hollow, nanotubes with interesting optical properties. The molecular packing of the dyes inside the nanotubes, however, remains elusive. https://www.selleckchem.com/products/pi4kiiibeta-in-10.html To reveal the structural features of the C8S3 nanotubes, we performed atomistic Molecular Dynamics simulations of preformed bilayers and nanotubes. We find that different packing arrangements lead to stable structures, in which the tails of the C8S3 molecules are interdigitated. Our results are verified by SAXS experiments. Together our data provide a detailed structural characterization of the C8S3 nanotubes. Furthermore, our approach was able to resolve the ambiguity inherent from cryo-TEM measurements in calculating the wall thickness of similar systems. The insights obtained are expected to be generally useful for understanding and designing other supramolecular assemblies.In tumor immunotherapy, Treg cells are immunosuppressive cells. In general, the main strategy of chemo immune-therapy for Treg cells is to eliminate them using chemotherapy drugs combined with immune checkpoint inhibitors. However, the dead Treg cells still exert immunosuppressive effects via the nucleoside adenosine pathway. To improve immunosuppression, we designed a nanosystem to deliver synthetic chemotherapeutics and immune activators. The homemade curcumin analog (CA) was encapsulated by α-lactalbumin (α-LA), and the Treg cell specific antibody (mAb), as a therapeutic agent, was linked to the drug-loaded protein via matrix metalloproteinase-responded peptide (P). After the cleavage peptide responded to matrix metalloproteinase (MMP-2), the CA@α-LA-P-mAb nanoparticles were separated into CA@α-LA and antibody, which can specifically enter cancer cells and Treg cells via membrane fusion and Nrp-1 receptors, respectively. Finally, we found that CA can not only lead to cell death by the chondriosome apoptosis approach but also reduce the production of Treg cells by inhibiting the expression of foxp3 (a key transcription factor of Treg cells). In addition, specific antibodies can improve the immunosuppression of existing Treg cells. The combined effect of CA and antibodies amplifies the role of chemotherapy in metastatic breast cancer.
The interaction of water with small alcohols can be used as a model for understanding hydrophobic solvation of larger and more complex amphiphilic molecules. Despite its apparent simplicity, water/ethanol mixtures show important anomalies in several of their properties, like specific heat or partial molar volume, whose precise origin are still a matter of debate. Here we report high-resolution thermal conductivity, compressibility, and IR-spectroscopy data for water/ethanol solutions showing three distinct regions of solvation, related to changes in the H-bond network. Notably, the thermal conductivity shows a surprising increase of ≈3.1% with respect to pure water at dilute concentrations of ethanol (x = 0.025), which suggests a strengthening of H-bond network of water. Our results prove that the rate of energy transfer in water can be increased by hydrophobic solvation, due to the cooperative nature of the H-bond network.Designing efficient and low-cost electrocatalysts for the hydrogen evolution reaction (HER) is of great importance to advance water splitting technology towards practical applications. Herein, we report the preparation of IrCo nanoparticles supported on nitrogen-doped carbon (IrCo/NC) as a HER electrocatalyst in acidic and alkaline electrolytes. The IrCo/NC composite is obtained by pyrolyzing an Ir-doped Co(OH)2 precursor on g-C3N4, and is endowed with N-doped carbon and uniform IrCo alloy nanoparticles via a crystal confinement resulting from the Ir-doping into the Co(OH)2 layer. Electrocatalytic analysis shows that the IrCo/NC electrode requires low overpotentials of 32 mV at 10 mA cm-2 in 0.5 M H2SO4 and 33 mV in 1 M KOH, which are superior to those of the Co/NC and IrCo alloys that are free of Ir-doping or N-doped carbon. The results provide a strategy for designing and preparing active noble-transition bimetallic alloy electrocatalysts as efficient HER catalysts.The development of anode materials is critical to the success of sodium ion batteries (SIBs). Because of the size difference between Li and Na, the commercial anode material graphite in Li-ion batteries does not work for Na-ion batteries. Thus, it will be ideal if some universal anode materials could work for both Li- and Na-ion batteries with high performance. Inspired by a recent study on the high performance of a 2D-Si2BN sheet as an anode material for Li-ion batteries, we design a three dimensional (3D) porous structure by using the nanoribbons of a Si2BN sheet as building blocks. Based on the state-of-the-art ab initio calculations, we find that the resulting 3D porous Si2BN structure is stable chemically, dynamically and thermally, exhibiting a high specific capacity of 512.42 (341.61 mA h g-1), a low voltage of 0.27 V (0.15 V), a small volume expansion of 2.5% (2.7%), and a low migration energy barrier of 0.44 eV (0.19 eV) for Li- (Na-) ion batteries. These intriguing features, together with the light mass and rich abundance of Si, B and N, suggest that the 3D porous Si2BN structure is a promising candidate for the anode material of both Li- and Na-ion batteries.This report describes the synthesis of organoselenyl isoquinolinium imides through a tandem cyclization between N'-(2-alkynylbenzylidene)hydrazides and diselenides. The reaction was carried out at room temperature under an ambient atmosphere using cheap iron(iii) chloride as the metallic source. The strategy shows good tolerance to a broad range of N'-(2-alkynylbenzylidene)hydrazides and diselenides, and forms C-N and C-Se bonds in one step. The obtained product is further transformed into a bioactive H-pyrazolo[5,1-a]isoquinoline skeleton easily via a silver catalyzed [3 + 2] cycloaddition.Self-assembled nanostructures arise when building blocks spontaneously organize into ordered aggregates that exhibit different properties compared to the disorganized monomers. Here, we study an amphiphilic cyanine dye (C8S3) that is known to self-assemble into double-walled, hollow, nanotubes with interesting optical properties. The molecular packing of the dyes inside the nanotubes, however, remains elusive. https://www.selleckchem.com/products/pi4kiiibeta-in-10.html To reveal the structural features of the C8S3 nanotubes, we performed atomistic Molecular Dynamics simulations of preformed bilayers and nanotubes. We find that different packing arrangements lead to stable structures, in which the tails of the C8S3 molecules are interdigitated. Our results are verified by SAXS experiments. Together our data provide a detailed structural characterization of the C8S3 nanotubes. Furthermore, our approach was able to resolve the ambiguity inherent from cryo-TEM measurements in calculating the wall thickness of similar systems. The insights obtained are expected to be generally useful for understanding and designing other supramolecular assemblies.In tumor immunotherapy, Treg cells are immunosuppressive cells. In general, the main strategy of chemo immune-therapy for Treg cells is to eliminate them using chemotherapy drugs combined with immune checkpoint inhibitors. However, the dead Treg cells still exert immunosuppressive effects via the nucleoside adenosine pathway. To improve immunosuppression, we designed a nanosystem to deliver synthetic chemotherapeutics and immune activators. The homemade curcumin analog (CA) was encapsulated by α-lactalbumin (α-LA), and the Treg cell specific antibody (mAb), as a therapeutic agent, was linked to the drug-loaded protein via matrix metalloproteinase-responded peptide (P). After the cleavage peptide responded to matrix metalloproteinase (MMP-2), the CA@α-LA-P-mAb nanoparticles were separated into CA@α-LA and antibody, which can specifically enter cancer cells and Treg cells via membrane fusion and Nrp-1 receptors, respectively. Finally, we found that CA can not only lead to cell death by the chondriosome apoptosis approach but also reduce the production of Treg cells by inhibiting the expression of foxp3 (a key transcription factor of Treg cells). In addition, specific antibodies can improve the immunosuppression of existing Treg cells. The combined effect of CA and antibodies amplifies the role of chemotherapy in metastatic breast cancer.
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