Construction of a novel electrochemical biosensor based on a mesoporous silica/oriented graphene oxide planar electrode for detecting hydrogen peroxide.

A constant magnetic field (CMF) was used to arrange the orientation of graphene oxide (GO) which was modified on a self-made screen-printed electrode. We evaluated the efficiency of this method for potential analytical application towards the sensing of hydrogen peroxide (H2O2). Mesoporous silica (MS)-encapsulated horseradish peroxidase (HRP) was immobilized on the electrode with vertically arranged GO to construct an H2O2 sensor (denoted as CMF/GO/HRP@MS).

[Degradation Characteristics of Three Aniline Compounds in Simulated Aerobic Sewage Treat System].

The removal rates of 4-nitroaniline, 4-isopropyl aniline and 2-chloro-4-nitroaniline under different hydraulic retention time (HRT) were tested by employing a simulation method of aerobic biochemical sewage treatment technology in this study. The results showed that when HRT was 6 h, 12 h, and 24 h, the removal rates of dissolved organic carbon (DOC) were 70.2%, 80.

(S)-Ethyl 2-[4-(6-chloro-quinoxalin-2-yl-oxy)phen-oxy]propanoate.

In the mol-ecule of the title compound, C(19)H(17)ClN(2)O(4), the quinoxaline ring system is planar [maximum deviation = 0.013 (3) Å] and oriented at a dihedral angle of 80.18 (3)° with respect to the benzene ring.

Synthesis of fluorous tags for incorporation of reducing sugars into a quantitative microarray platform.

Carbohydrate microarrays can map out key interactions of carbohydrates and proteins in a high-throughput manner, but require the inclusion of a range of sugars for their optimal use. Here we present the synthesis and use of a new hydroxylamine-modified fluorous tag that allows the facile incorporation of reducing sugars into a noncovalent fluorous-based microarray after simple purification by fluorous solid-phase extraction (FSPE). The microarray supports quantitative screening against carbohydrate-binding proteins.

Bundle-shaped cyclodextrin-Tb nano-supramolecular assembly mediated by C60: intramolecular energy transfer.

A bundle-shaped nano-supramolecular assembly possessing numerous luminescent cyclodextrin-Tb polyads and photosensitizing C(60) units has been constructed through the end-to-end inclusion complexation of cyclodextrin cavities with C(60)s, and its properties have been comprehensively characterized. Further investigations on the luminescence properties of the cyclodextrin-Tb polyad and the bundle-shaped assembly demonstrate that a pyridine --> Tb --> C(60) intramolecular energy transfer process is operative when a solution of the assembly is exposed to UV light.

Secondary assembly of bile salts mediated by beta-cyclodextrin-terbium(III) complex.

A fluorescent cyclodextrin-Tb(III) complex is successfully synthesized and can include bile salts in its hydrophobic cavities. Therefore, it can efficiently induce the secondary assembly of small bile salt primary micelles to large micelle aggregates, and the aggregation process can be easily observed by transmission electron microscopy (TEM) and fluorescence microscopy.

Cyclodextrins as carriers for cinchona alkaloids: a pH-responsive selective binding system.

A series of cyclodextrin-cinchona alkaloid inclusion complexes were prepared from beta-cyclodextrin, heptakis(2,6-di-O-methyl)-beta-cyclodextrin and heptakis(2,3,6-tri-O-methyl)-beta-cyclodextrin and four cinchona alkaloids in ca. 90% yields, and their inclusion complexation behavior was investigated at pH 7.2 and 1.

Inclusion complexes of azadirachtin with native and methylated cyclodextrins: solubilization and binding ability.

The inclusion complexation behavior of azadirachtin with several cyclodextrins and their methylated derivatives has been investigated in both solution and the solid state by means of XRD, TG-DTA, DSC, NMR, and UV-vis spectroscopy. The results show that the water solubility of azadirachtin was obviously increased after resulting inclusion complex with cyclodextrins. Typically, beta-cyclodextrin (beta-CD), dimethyl-beta-cyclodextrin (DMbetaCD), permethyl-beta-cyclodextrin (TMbetaCD), and hydroxypropyl-beta-cyclodextrin (HPbetaCD) are found to be able to solubilize azadirachtin to high levels up to 2.

Binding behavior of aliphatic oligopeptides by bridged and metallobridged bis(beta-cyclodextrin)s bearing an oxamido bis(2-benzoic) carboxyl linker.

beta-Cyclodextrin dimers bearing an oxamido bis(2-benzoic) carboxyl linker (1) or its metal complexes (2 and 3) were newly synthesized, and their inclusion complexation behavior with a series of representative aliphatic oligopeptides, i.e., Leu-Gly, Gly-Leu, Gly-Pro, Glu-Glu, Gly-Gly, Gly-Gly-Gly, and Glu(Cys-Gly), was elucidated by means of UV/vis, circular dichroism, fluorescence, and 2D NMR spectroscopy in Tris-HCl buffer solution (pH 7.

Inclusion complexes of paclitaxel and oligo(ethylenediamino) bridged bis(beta-cyclodextrin)s: solubilization and antitumor activity.

The inclusion complexation behavior of paclitaxel with a series of oligo(ethylenediamino) bridged bis(beta-cyclodextrin)s possessing bridge chains in different length (1-4) has been investigated in order to improve the water solubility of paclitaxel. It is found that only the long-tethered bis(beta-cyclodextrin)s 1 and 2 can form the inclusion complexes with paclitaxel, which are characterized by NMR, SEM, XRD, FT-IR, TG-DTA, DSC, and microcalorimetry technology. The results obtained show that bis(beta-cyclodextrin)s 1 and 2 are able to solubilize paclitaxel to high levels up to 2 and 0.

Interaction between beta-cyclodextrin and 1,10-phenanthroline: uncommon 2:3 inclusion complex in the solid state.

The crystallographic structure of the complex formed by beta-cyclodextrin with 1,10-phenanthroline has been studied by X-ray diffraction. The result shows that the complex adopts an uncommon 2:3 stoichiometry in solid state, that is, every complex unit contains three 1,10-phenanthroline molecules and two beta-cyclodextrin molecules, where two 1,10-phenanthroline molecules individually occupy two cyclodextrin cavities, and the third guest molecule is located in the interstitial space between two head-to-head cyclodextrin molecules. The intermolecular hydrogen bonds between the adjacent complex units further link these individual monomers to a channel-type assembly.

Molecular binding behavior of pyridine-2,6-dicarboxamide-bridged bis(beta-cyclodextrin) with oligopeptides: switchable molecular binding mode.

Bridged bis(beta-cyclodextrin) 1 with a pyridine-2,6-dicarboxamide linker was synthesized, and its inclusion complexation behavior with some aliphatic oligopeptides was investigated in aqueous buffer solution of pH 2.0 and 7.2 at 25 degrees C by means of circular dichroism, fluorescence, and 2D NMR techniques.

Inclusion complexation and solubilization of paclitaxel by bridged bis(beta-cyclodextrin)s containing a tetraethylenepentaamino spacer.

A novel water-soluble paclitaxel complex has been prepared by inclusion complexation with bridged bis(beta-cyclodextrin)s and characterized by means of (1)H NMR, SEM, powder X-ray diffraction patterns, TG-DTA, DSC, FT-IR, and 2D NOESY. The cyclodextrins were able to solubilize paclitaxel to levels as high as 2 mg/mL. Furthermore, the cytotoxicity of the novel complexes was assessed using a K562 leukemia cell line which indicated that drug concentrations of 10 pg/mL elicited an inhibitory effect.