An efficient and safe gene delivery system remains a challenge in the development of gene ***-based gene nanoparticles are a typical non-viral gene delivery system,which are able to transfect cells in vitro and in ***...
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An efficient and safe gene delivery system remains a challenge in the development of gene ***-based gene nanoparticles are a typical non-viral gene delivery system,which are able to transfect cells in vitro and in *** paper reported a facile method for constructing biodegradable multilayers via layer-by-layer self-assembly,in which the polycation-based gene nanoparticles were *** this surface-mediated delivery system,adherent cells on the multilayer could be transfected in *** nanoparticles-loaded multilayers transfect cells with higher efficiency than naked DNA-loaded multilayers because of the complex configuration of the *** nanoparticles/PGA multilayers constructed on the scaffold surface could also realize in situ transfection on the adherent *** well-structured,easy-processed multilayers may provide a novel approach to precisely controlled delivery of gene nanoparticles,which may have potential applications for gene therapy in tissue engineering and medical implants.
A novel organic electron acceptor, N,N′-dipyrimidinyl-3,4,9,1.-perylene-tetracarboxylic diimide (DMP), was designed and synthesized. The molecular structure was characterized by FTIR spectrum and elemental analysis. ...
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A novel organic electron acceptor, N,N′-dipyrimidinyl-3,4,9,1.-perylene-tetracarboxylic diimide (DMP), was designed and synthesized. The molecular structure was characterized by FTIR spectrum and elemental analysis. By cyclic voltammetry measurements, DMP was found to possess a lower LUMO energy level than N,N′-diphenyl-3,4,9,1.-perylene-tetracarboxylic diimide due to the stronger electron-withdrawing pyrimidinyl group than the phenyl group. Fluorescence quenching is observed in a dual-layer film consisting of a DMP layer and a C60 layer and was attributed to the charge transfer at the interface due to the energy level offset between DMP and C60.
Spherical molecular brushes with amphiphilic heteroarms were facilely synthesized by grafting the arms of hydrophobic 2-azidoethyle palmitate and hydrophilic monoazide-terminated poly(ethylene glycol) onto the core of...
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Spherical molecular brushes with amphiphilic heteroarms were facilely synthesized by grafting the arms of hydrophobic 2-azidoethyle palmitate and hydrophilic monoazide-terminated poly(ethylene glycol) onto the core of alkyne-modified hyperbranched polyglycerol (HPG) with high molecular weight (Mn=1.2 kDa) via one-pot parallel click *** parallel click grafting strategy was demonstrated to be highly efficient (~1.0%),very fast (~ 2 h) and well controllable to the amphilicity of molecular *** adjusting the feeding ratio of hydrophobic and hydrophilic arms,a series of brushes with different arm ratios were readily *** resulting miktoarms hyperbranched polymer brushes (HPG-g-C1./PEG350) were characterized by hydrogen-nuclear magnetic resonance (1. NMR),Fourier transform infrared (FT-IR) spectroscopy,gel permeation chromatography (GPC),and differential scanning calorimetry (DSC) *** spherical molecular brushes showed high molecular weights up to 230 kDa,and thus could be visualized by atomic force microscopy (AFM).AFM and dynamic laser light scattering (DLS) were employed to investigate the self-assembly properties of amphiphilic molecular brushes with closed proportion of hydrophobic and hydrophilic *** brushes could self-assemble hierarchically into spherical micelles,and network-like fibre structures,and again spherical micelles by addition of n-hexane into the dichloromethane or chloroform solution of *** addition,this kind of miktoarms polymer brush also showed the ability of dye loading via host-guest encapsulation,which promises the potential application of spherical molecular brushes in supramolecular chemistry.
Wettability of a solid surface is highly important to its practical application,especially for the surface that shows thermoresponsive *** this paper,we describe a thermo-responsive stick-slip behavior of water drople...
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Wettability of a solid surface is highly important to its practical application,especially for the surface that shows thermoresponsive *** this paper,we describe a thermo-responsive stick-slip behavior of water droplets on the surfaces of poly(N-isopropylacrylamide)(PNIPAM)-grafted polypropylene *** emission scanning electron microscope(FESEM) images elucidate that the morphology of PNIPAM-grafted membrane surface is thermo-responsive,i.e.,the surface becomes rougher above the lower critical solution temperature(LCST) of *** the surface of nascent polypropylene membranes,the water droplet shows a smooth motion resulting in advancing and receding water contact angles of 1.1. and ~65°,*** the PNIPAM-grafted membrane surfaces,the water droplet shows a stick-slip pattern above the LCST,whereas it advances smoothly below the *** phenomenon is reproducible and can be ascribed to the energy barriers enhanced by the shrink of PNIPAM chains above the *** also find that the slip contact angle decreases from 1.2° to 92° after several stick-slip *** decrease is attributed to the water adsorption on the grafted PNIPAM layer,which is confirmed by the continuous decrease of the receding water contact angle.
Discrete ion-pair complexes [Ln(EDBP)2(DME)Na(DME)3] [Ln=Er (1., Yb (2), Sm (3)] have been synthesized by the reaction between sodium salt of 2,2'-ethylidene-bis(4,6-di-tert-butylphenol)(EDBPH2) and Ln(BH4)3.3;...
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Discrete ion-pair complexes [Ln(EDBP)2(DME)Na(DME)3] [Ln=Er (1., Yb (2), Sm (3)] have been synthesized by the reaction between sodium salt of 2,2'-ethylidene-bis(4,6-di-tert-butylphenol)(EDBPH2) and Ln(BH4)3·3THF (Ln=Er, Yb, Sm) followed by centrifugation and recrystalization. The complexes were characterized by elemental analysis and FT-IR, and the bonding model of these compounds was confirmed by X-ray single crystal diffraction for complex 1. It was found that four O atoms in two biphenol ligands as well as two O atoms in one ethylene glycol dimethyl ether (DME) molecule connect to the center rare earth metal atom, while sodium exists as counterpart cation to balance the charge. Complexes 1.3 can all be used as single component initiators for the ring-opening polymerization of ε-caprolactone.
Fluorescent hyperbranched polymers (FHBPs),which combine the versatile fluorescent property with unique characteristics of hyperbranched architecture,are desirable candidates for stimulus responsive *** review demonst...
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Fluorescent hyperbranched polymers (FHBPs),which combine the versatile fluorescent property with unique characteristics of hyperbranched architecture,are desirable candidates for stimulus responsive *** review demonstrates the structure and environment-dependent emission behaviors of a series of *** active FHBPs showing opposite performance to ACQ effect are used to sensitively detect explosives and a superamplification effect is *** designed FHBPs can complex with metal ions,leading to fluorescence turn-off due to complex quenching *** protonation of amino-containing FHBPs exhibits pH-dependent fluorescence responses to solution *** FHBPs containing responsive moieties are photo-and thermo-sensitive,and show potential applications as smart materials.
Rheological measurement has been an effective method to characterize the structure and properties for multiphase/multi-component polymers, owing to its sensitivity to the structure change of hetero- geneous systems. I...
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Rheological measurement has been an effective method to characterize the structure and properties for multiphase/multi-component polymers, owing to its sensitivity to the structure change of hetero- geneous systems. In this article, recent progress in the studies on the morphology/structure and rheological properties of heterogeneous systems is summarized, mainly reporting the findings of the authors and their collaborators, involving the correlation between the morphology and viscoelastic relaxation of LCST-type polymer blends, the microstructure and linear/nonlinear viscoelastic behavior of block copolymers, time scaling of shear-induced crystallization and rheological response of poly- olefins, and the relationship between the structure/properties and rheological behavior of filled polymer blends. It is suggested that a thorough understanding of the characteristic rheological response to the morphology/structure evolution of multiphase/multi-component polymers facilitates researchers’ op- timizing the morphology/structure and ultimate mechanical properties of polymer materials.
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