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Cyclodextrins (CDs) are regarded as one kind of the most important and promising macrocyclic oligosaccharides, which contain hydrophobic internal cavities capable of hosting various guest molecules. CDs are water-soluble, non-toxic, commercially available as well as low-cost. Because of these favorable characteristics, cyclodextrin chemistry has created a great number of interesting works covering different fields, in particular CD-based porous nanocapsules (CDPNCs). Chemical cross-linking is an important way developed to prepare CDPNCs. CDPNCs can be obtained using different cross-linkers and preparation methods, such as homogeneous method, miniemulsion polymerization, and emulsion-solvent evaporation method. Because of cross-linking, a three-dimensional network is built which forms the porous structure in CDPNCs with the cavities of CDs. Attributed to the porous structure, CDPNCs exhibit excellent performances in encapsulation of targeted molecules and realization of controllable release, indicating a promising prospect in applications such as drug delivery systems and environment protection. [ABSTRACT FROM AUTHOR]

Review: synthesis using different cross-linkers and preparation methods; 86 refs. [ABSTRACT FROM AUTHOR]

Cyclodextrins (CDs) show functionality, biocompatibility, and host-guest inclusion capacity with a variety of molecules. These unique properties offer great potential for the exploitation of CDs as drug delivery systems. An easy, green, and effective synthetic approach was described to develop CD-based porous nanospheres (CDPNSs) with a size distribution from 100 to 400 nm. A new cross-linker tris(2-aminoethyl)amine was used to cross-link modified β-CD at room temperature. The resulting CD-based polymers (CDPs) were reshaped from a random morphology into a spherical shape during a dialysis process, and CDPNSs were obtained. The morphologies of CDPs and CDPNSs were observed with scanning electron microscopy. The average diameter and the size distribution of CDPNSs were determined by dynamic light scattering. The structures of the resulting products were characterized by using Fourier transform infrared spectroscopy, 1H NMR spectroscopy, solid-state 13C CP/MAS NMR spectroscopy, and X-ray diffraction. Furthermore, a study was conducted on drug loading and in vitro release behavior of CDPNSs, which was monitored by ultraviolet spectroscopy. The prepared CDPNSs show the potential as drug delivery systems. [ABSTRACT FROM AUTHOR]

Graphene attracts more and more scientists and researchers owing to its superior electronic, thermal, and mechanical properties. For material scientists, graphene is a kind of versatile building blocks, and considerable progress has been made in recent years. Graphene-based hybrid materials have been prepared by incorporating inorganic species and/or cross-linking of organic species through covalent and/or noncovalent interactions. The graphene-based hybrid materials show improved or excellent performance in various fields. In this review, we summarize the synthesis of graphene and graphene-based hybrid materials, and their applications in energy storage and conversion. [ABSTRACT FROM AUTHOR]

In this work, a novel and simple flexible aromatic multi-carboxylate compound N, N′-(4,4′-biphenylyl) iminodiacetic acid (BP-IDA) was synthesized, with which two new stable metal-IDA gels (denoted as MIG1 and MIG2) with three-dimensional network structures have been prepared successfully by employing Cr3+ and Al3+ as the metal ions, respectively. The rheological performance was investigated by means of dynamic rheology measurement. The morphology and microstructure were characterized by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction technique. Nitrogen sorption isotherm measurement suggests that the MIG1 aerogel has considerable porosity with the Brunauer-Emmett-Teller specific surface area up to 760 m2·g−1. Owing to easy preparation, good stability, and three-dimensional network structure, the as-prepared metal-organic gels will possess potential applications in separation, catalysis, and drug delivery. [ABSTRACT FROM AUTHOR]

An acid-resistant catalyst composed of nickel embedded in N-doped porous carbon is developed for the catalytic hydrogenation of nitrobenzene (NB) to p-aminophenol (PAP). The catalyst, due to a special electron donation from nickel to the N-doped porous carbon, shows an excellent catalytic performance and stability in sulphuric acid solution. [ABSTRACT FROM AUTHOR]

Accurate measurement of inter-peptide interactions is beneficial for in-depth understanding disease-related protein folding and peptide aggregation, and further for designing and selecting potential peptide drugs to the target antigen. Herein, we demonstrate a 3D polyrotaxane (PRX) surface for detecting peptides interactions by surface plasmon resonance imaging (SPRi). This surface is supramolecular self-assembly monolayer (SAM) structure fabricated by threading α -cyclodextrans ( α -CD) through a linear polyethylene glycol (PEG) chain fixed on gold chip surface to form pseudopolyrotaxane, and further capping the pseudopolyrotaxane with bulky terminated group to form PRX film. The hydroxyl groups of α -CD can provide more active sites to increase molecules immobilization density, and PEG chain has unique protein non-fouling feature. We chose Alzheimer's disease marker β -amyloid 40 (A β 40) as model peptide, and detected the interaction between it and its inhibitors KLVFFK6 by SPRi. As a striking result, the specific adsorption of KLVFFK6 solution at the concentration of 352 μM on A β 40-PRX was 700 RU, whereas PEG SAM surface gave no significant binding. Interaction between other lower molecular weight peptides was detected via PRX surface, and the relatively weak interactions ( K D =1.73×10 −4 M) between LPFFD ( Mw =0.6 kDa) and amylin20-29 ( Mw =1.0 kDa) are successfully detected. [ABSTRACT FROM AUTHOR]

A series of benzimidazole-linked porous polymers are obtained by the condensation reaction between the o-aminobenzol end groups of building blocks (2,3,6,7,10,11-hexaaminotriphenylene, 3,3′-diaminobenzidine or 1,2,4,5-benzenetetraamine) and the aldehyde groups of building blocks [terephthalicaldehyde, 4,4′-biphenyldicarboxaldehyde, 1,3,5-tris(4-acetylphenyl)benzene or 1,3,5-tris(4-formylbiphenyl)amine] in one-pot synthesis without employing any catalyst or template. The existence of the imidazole ring in the obtained polymers could be identified by Fourier transform infrared and solid-state 13C CP/MAS NMR spectroscopy. The sphere-shaped morphology of the obtained polymers is observed through scanning electron microscopy. The polymers possess Brunauer-Emmett-Teller specific surface area values over 600 m2·g−1, showing hydrogen storage (up to 1.6 wt%, at 77 K and 1×105 Pa) and carbon dioxide capture (up to 12.6 wt%, at 273 K and 1×105 Pa) properties. Such polymers would possess good performance in the applications of gas storage and separation. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO)-wrapped gold nanoparticles (Au NPs) hybrid materials are constructed via one-pot sonochemical synthesis and self-assembly, using ethylene glycol as the reducing agent. The synthesis process above took only 1 h, and the obtained hybrid materials exist as spheres wrapped with gauze-like GO sheets via ionic interaction-based self-assembly. The GO sheets are helpful for the well dispersion of the Au NPs. Furthermore, these materials possess enhanced photocatalytic activity under visible light irradiation, owing to the synergistic effect of the two components in the hybrid materials. Our work may provide a convenient approach to control the size and morphology of the Au NPs for the synthesis of GO-wrapped hybrid materials, which opens up a feasible way to synthesize metal NPs/GO composites. Moreover, this method might lead to developing of a broad class of new functionalized materials wrapped with GO sheets. [ABSTRACT FROM AUTHOR]

Graphene-MnO (GMNO) hybrid porous material is prepared by a hydrothermal method and its performance in carbon dioxide adsorption is investigated. In the synthesis of the GMNO materials, MnO(OH) colloid obtained by the hydrolysis of Mn in basic solution was using as the precursor of the MnO. After a hydrothermal reaction of the mixture of graphene oxide (GO) and MnO(OH), GO was reduced into graphene and the MnO(OH) was transformed into MnO with enhanced crystallization. X-ray diffraction, thermal gravimetric analysis, transmission electron microscopy, infrared spectra and Raman spectroscopy were taken to characterize the hybrid material. The porosity and the carbon dioxide adsorption ability are measured by gas sorption analysis, in which the as-prepared GMNO hybrid materials exhibit a specific surface area ranging from 140 to 680 m g and a maximum carbon dioxide capacity of about 11 wt%. [ABSTRACT FROM AUTHOR]

Abstract: A cost-effective and efficient route for graphene oxide (GO) patterning through site-selective deposition of GO onto a photopatterned self-assembled monolayer (SAM) of octadecylphosphonic acid on the surface of native oxide of titanium was demonstrated. In this process, SAMs on titanium oxide was first patterned via ultraviolet light exposure through a mask, subsequent drop-casting of GO aqueous dispersion on the substrate resulted in the site-selective deposition of GO on the hydrophilic areas. The formation of GO patterns is evidenced by Raman mapping. Atomic force microscopy studies indicate that the thickness of patterned GO can be controlled by adjusting the concentration of the GO dispersion. Scanning electron microscopy, and inverted fluorescence microscopy of large area GO patterns demonstrate this process is scalable and that the fluorescent property of nanoscale GO sheets is still reserved after deposition. [Copyright &y& Elsevier]

A simple and efficient route for quantum dot (QDs) patterning using self-assembled monolayers (SAMs) as templates is described. By means of a laser direct-writing (LDW) technique, SAMs of octadecylphosphonic acid formed by adsorption on native oxide layer of titanium film were patterned through laser-induced ablation of the SAM molecules. This technique allows the creation of chemical-specific patterns accompanied by slight change in the topography. Using atomic force microscopy and friction force microscopy, the dependence of feature size and characteristics on the irradiation dose was demonstrated. Upon immersion of a substrate with patterned SAMs bearing thiol as the terminal group into a dispersion of QDs resulted in the assembly of QDs on the specific thiol-terminated areas. Patterns of QDs with different photoluminescent wavelength were generated. The LDW technique, which is convenient and flexible due to its path-directed and maskless fabrication process, provided a new powerful approach for patterning materials on surfaces for various applications. [ABSTRACT FROM AUTHOR]