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Despite that either non-covalent or covalent attachment of hydrophilic polymers or surfactants onto nanodiamonds (NDs) could overcome the shortcomings of being a drug delivery system, it is hard to draw a definite conclusion which strategy is more effective. Hence, with the purpose of comparing the influence of different coating approach of NDs on the oral delivery efficiency of water-insoluble model drug curcumin (CUR), NDs were firstly modified with d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) via non-covalent or covalent conjugation method, and then loaded with CUR (CUR@NDs-COOH/TPGS or CUR@NDs-TPGS). In comparison with the core-shell-structured CUR@NDs-COOH/TPGS, CUR@NDs-TPGS were irregular in shape with dense TPGS film, and exhibited smaller size, more negatively potential, and higher drug loading efficiency. The covalent connection group also showed higher anti-cancer activity, cellular uptake, and permeability through the Caco-2 cell monolayers, as well as favorable distribution, penetration, and retention in rat intestines. The oral bioavailability study in rats demonstrated that CUR@NDs-TPGS showed significantly greater Cmax and AUC0−t in contrast with CUR suspension and the TPGS-coated ones, respectively. The findings illustrated that covalent grafting TPGS onto the surface of NDs possesses better efficacy and biocompatibility on oral delivery of poorly soluble drug CUR than pristine and non-covalent coated nanoparticles. [ABSTRACT FROM AUTHOR]

The Ti-heteropolyacid H4[Ti(H2O)TiW11O39]·7H2O (TiW11Ti) loading TiO2 with different contents was prepared using dipping method. The TiW11Ti/TiO2 hybrid was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and diffuse reflectance spectra (DRS). The photocatalytic performance of TiW11Ti/TiO2 hybrid was investigated by rapid degradation of X-3B as simulated wastewater under xenon light irradiation. The different loading amount of TiW11Ti exhibited different activity. The order of different loading weights of TiW11Ti was as follows: 43 wt% TiW11Ti > 31 wt% TiW11Ti > 50 wt% TiW11Ti > 20 wt% TiW11Ti. The results revealed that the rapid degradation process followed the first-order kinetic reaction according to Langmuir equation. The TiW11Ti/TiO2 hybrid exhibited highly efficient photocatalytic activity, which was potential for environmental purification. [ABSTRACT FROM AUTHOR]

Two new solid hybrid molecular materials [PyPS]HPWVO and [PyPS]HPWVO have been synthesized from 1-(3-sulfonic group) propyl-pyridine ionic liquid cation and tungstovanadophosphoric anion with the Dawson structure. They were characterized by element analysis, impedance spectroscopy (IS), IR- and UV-spectroscopy. The formation of the hybrid molecular compounds with the Dawson structure was showed. Ion conductivity of [PyPS]HPWVO and [PyPS]HPWVO are 3.99 × 10 and 7.37 × 10 S cm at 18°C and 55% relative humidity respectively. The activation energies of proton conductivity are 28.2 and 26.7 kJ mol respectively. [ABSTRACT FROM AUTHOR]

A novel kind of organic-inorganic material, (TOAMe)[In(HO)PWO] (TOAMe = trioctylmethylammonium), is synthesized as white oily product from polyoxometalate-type ionic liquid with Dawson structure and simple quaternary ammonium ionic liquid. It was characterized by IR, UV, X-ray diffraction, and thermogravimetric-differential thermal analysis. The determination of (TOAMe)[In(HO)PWO] shows that it has a high conductivity with 1.25 × 10 S cm at 24 °C. In addition, its electrochemical properties were also investigated by the cyclic voltammetric studies. And then we released that the indium in the complexes can undergo reduction in dimethylformamide, which is unlikely in the water solution as a simple hydrated ion. [ABSTRACT FROM AUTHOR]

The ruthenium-substituted polyoxometallic acid H[Ru(HO)FeWO]·18HO was synthesized by stepwise acidification and stepwise addition of solutions of the component elements, and an ion-exchange-cooling method. The product was characterized using inductively coupled plasma spectrometry (ICP), Infrared Spectroscopy (IR), Ultraviolet Spectroscopy (UV), and X-ray diffraction (XRD). The results show that this complex has the Keggin structure. The determination of the thermal stability and proton conductivity of this polyoxometallic acid was carried out by a thermogravimetric-differential thermal analysis (TG-DTA) and electrochemical impedance spectroscopy (EIS). [ABSTRACT FROM AUTHOR]

A new solid high-proton conductor, H[Ga(HO)PWO]·18HO, a substituted heteropoly acid with Dawson structure, has been synthesized by the degradation/ion-exchange/freezing method. The product was characterized by potentiometric titration, chemical analysis, IR, UV, XRD and TG-DTA. Complex impedance measurements show a high conductivity (5.44×10 S/cm at 50°C), with an activation energy for proton conduction of 36.04 kJ/mol. The mechanism of proton conduction is the Vehicle mechanism. [ABSTRACT FROM AUTHOR]