A dual-responsive superparamagnetic Fe3O4/Silica/PAH/PSS material used for controlled release of chemotherapeutic agent,keggin polyoxotungstate,PM–19

A bicontrollable drug release system was developed by layer-by-layer assembly of poly(allylamine hydrochloride) (PAH)/sodium poly(styrene sulfonate) (PSS) multilayers onto a Fe₃O₄/SiO₂ composite core. The saturated magnetization of this system reaches up to 38.6 emu/g at RT, making targeting easily controlled by an external magnetic field. Meanwhile, the packing of the polyelectrolyte multilayers is sensitive to pH values, generating a pH-switch on-off mode for the release of loaded drugs. In this specific case, the release of a chemotherapeutic polyoxometalate K₇Ti₂W₁₀PO₄₀·6H₂O (PM–19) was tested. Transmission electron microscopy (TEM) was used to examine the nanostructure of the composite drug release system. UV–vis absorption was used to monitor the drug release. Fourier transform infrared (FTIR), Powder X–ray diffraction, and Elemental analyses were used to study the composition of tested systems. The structure and composition of the composite system was also studied using magnetism measurement and nitrogen adsorption–desorption.     

稀土双(11-钨硅酸)钾的质子导电性研究(英)

研究了K13［Ln（SiW11O39）2］nH2O（Ln=La，Ce，Pr，Nd，Sm，Gd）的质子导电性研究表明其导电性不仅与物质本性有关，也与外界条件如温度、频率等有关，不同结构的杂多化合物给出不同结构的质子导电性．总结了质子导电性随温度、结晶水数目、频率的变化总趋势．基于实验数据得出一些重要结论，所得数据未见文献报道．     

Syntheses, characterization and catalytic reactivities of heteropolyanion-pillared clay of anions of Zn-Al type

Mono-substituted Keggin ions PW11O39Cr(H2O)4 , PW11TiO403 and PW11VO404 were intercalated between the layers of the clay of anions of Zn-Al type using the ion exchange method to obtain a new type of pillared layered microporous materials ZnAl-PW11Cr, ZnAl-PW11Ti and ZnAl-PW11V with basal spacing (1.48±0.02) run. On the basis of the MAS NMR results of 27A1 and 31P, a steric pillared layered structure model of orientation localization of PW11VO40,4- in the orientation in which the C2 axis of PW11VO404-is perpendicular to the host layer. It has been found that this kind of pillared layered microporous materials possess a higher catalytic activity for the esterification of acetic acid with n-butanol than H-type molecular sieves.     

α-Mangostin exhibits antidepressant-like effects mediated by the modification of GABAergic,serotonergic and dopaminergic systems

Abstract

The present study explored the antidepressant-like activity of α-mangostin (α-MG) and the possible mechanism in this process in the tail suspension test (TST) in mice. The results revealed that α-MG (5?mg/kg, i.p.) exhibited markedly antidepressant-like activity, which could be reversed by pretreatment with haloperidol (a non-selective D₂ receptor antagonist), bicuculline (a competitive GABA antagonist), p-chlorophenylalanine (an inhibitor of 5-HT synthesis). Meanwhile, α-MG also effectively increased the brain DA, 5-HT and GABA levels in mice exposed to TST, indicating that the antidepressant-like effect of α-MG might be mediated by the GABAergic, serotonergic and dopaminergic systems.

     

Synthesis and X-ray structure of [(H3O)(C14H20O5)2][Me2NH2]2 [PMo12O40] · 2C14H20O5 (C14H20O5 = benzo-15-crown-5; Me2NH = dimethylamine)

[(H₃O)(C₁₄H₂₀O₅)₂][Me₂NH₂]₂ [PMo₁₂O₄₀] · 2C₁₄H₂₀O₅ 1 was synthesized from benzo-15-crown-5 and H₃PMo₁₂O₄₀·24H₂O in N,N-dimethylformamide for the first time. 1 crystallizes in the monoclinic space group C2/c with a = 18.583(4), b = 25.510(5), c = 19.904(4) Å, = 94.66(3)° D _c = 2.124 mg/m³ for Z = 4. Refinement based on 7358 observed reflections led to a R1(wR2) = 0.0378(0.0761). The complex cation, [(H₃O)(C₁₄H₂₀O₅)₂]⁺, exhibits a sandwich structure by hydrogen-bonding in the mean distance of 2.955 Å. The anion, PMo₁₂O₄₀ ^3–, is a -Keggin structure.     

A New 1D Chain-like Complex Built Up of Cu-containing Sandwich Tungstogermanate

Two new tungstogermanates K₂Na₁₀[Cu₄(GeW₉O₃₄)₂] · 15.5H₂O (1) and K₄Na₆[Cu_3.5W_0.5(H₂O)₂(GeW₉O₃₄)₂] · 17H₂O (2) have been obtained by the conventional aqueous solution methods and characterized by IR, element analysis, electrochemistry and single-crystal X-ray analysis. Compound 1 is composed of the [Cu₄(GeW₉O₃₄)₂]¹²⁻ anions linked by two equivalent bonds of Cu–O–W, representing the first one-dimensional chain-like structure based on sandwich-type polyoxometalates by direct condensation to form oxo-bridged arrays of clusters. Compound 2 is a sandwich structure, consisting of two trivacant [GeW₉O₃₄]¹⁰⁻ units linked by a [Cu_3.5W_0.5(H₂O)₂] cluster, and the anions are linked by the K⁺ and Na⁺ to form a three-dimensional structure. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Structural characterization of two lanthanide complexes attached to [H<Subscript>2</Subscript>W<Subscript>12</Subscript>O<Subscript>40</Subscript>]<Superscript>6−</Superscript>

In this article, two compounds [H₂bpy][Ln(DMF)₄(H₂O)₃(Hbpy)][H₂W₁₂O₄₀] (Ln = La,Ce; DMF = N,N-dimethylformamide, bpy = 4,4′-bipyridine) have been synthesized and characterized by single-crystal X-ray diffraction, IR spectra, and TG analysis. X-Ray analysis showed that the [Ln(DMF)₄(H₂O)₃(Hbpy)]⁴⁺ unit is supported on the α-Keggin polyoxoanion [H₂W₁₂O₄₀]⁶⁻ via the surface bridging oxygen atom. The [H₂bpy][Ln(DMF)₄(H₂O)₃(Hbpy)][H₂W₁₂O₄₀] entity is further extended into 2D supramolecular networks with 1-D channels by hydrogen-bonding interactions, in which 4,4′-bipy ligands reside. To the best of our knowledge, these complexes represent the first examples of rare earth metal-organic complex-decorated α-metatungstate clusters. Furthermore, the electrochemical properties of these compounds have been studied via the method of bulk-modified carbon paste electrodes.     

Two multi-copper-containing heteropolyoxotungstates constructed from the lacunary Keggin polyoxoanion and the high-nuclear spin cluster

Two novel high-nuclear copper-substituted polyoxometalates, Na16[Cu14(OH)4(H2O)16(SiW8O31)4].20.5H2O (1) and K10Na14[Cu10(H2O)2(N3)4(GeW9O34)2(GeW8O31)2].30H2O (2), containing 14 Cu2+ ions and 10 Cu2+ ions, respectively, have been obtained in aqueous solution and characterized by IR, UV, TG, element analysis, electrochemistry, and single-crystal X-ray analyses. The polyoxoanion framework of 1 is composed of four [beta-SiW8O31] units connected by 14 Cu2+ ions to constitute a tetrameric compound. In 2, two [beta-GeW8O31] anions and two [B-alpha-GeW9O34] anions are connected together by a [Cu10(N3)4O32(H2O)2] {Cu10(N3)4} cluster to construct a novel tetrameric compound. The results of the electrocatalytic experiments reveal that the reduced species of 1 and 2 have electrocatalytic activities for nitrate reduction.     

Preparation and Characterization of Heteropoly Octadecamolybdodiphosphates

Heteropoly molybdophosphates with general formula M(?)P2Mo18O62 ·xH2O, where M = H+, K+, NH4+, Ca2+, Co2+, Ni2+, Cu2+, Zn2+ and Ag+, were prepared and characterlzed by elemental analysis, IR and UV spectrometry and thermal analysis. The solubilities of the compounds were examined. The IR spectra show that the countercations and the crystallization water have an influence upon the vibration frequencies of vMo-Oc and vMo-Oc-Mo·In the UV spectra, the charge-transfer bands are assigned to e→e and e→b2 transition. All the compounds decompose at 328-534℃.