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The five-membered heteroelement cluster THF·Cl2In(OtBu)3Sn reacts with the sodium stannate [Na(OtBu)3Sn]2 to produce either the new oxo-centered alkoxo cluster ClInO[Sn(OtBu)2]3 (1) (in low yield) or the heteroleptic alkoxo cluster Sn(OtBu)3InCl3Na[Sn(OtBu)2]2 (2). X-ray diffraction analyses reveal that in compound 1 the polycyclic entity is made of three tin atoms which together with a central oxygen atom form a trigonal, almost planar triangle, perpendicular to which a further indium atom is connected through the oxygen atom. The metal atoms thus are arranged in a Sn3In pyramid, the edges of which are all saturated by bridging tert-butoxy groups. The indium atom has a further chloride ligand. Compound 2 has two trigonal bipyramids as building blocks which are fused together at a six coordinate indium atom. One of the bipyramids is of the type SnO3In with tert-butyl groups on the oxygen atoms, while the other has the composition InCl3Na with chlorine atoms connecting the two metals. The sodium atom in 2 has further contacts to two plus one alkoxide groups which are part of a[Sn(OtBu)2]2 dimer disposing of a Sn2O2 central cycle. The hetero element cluster in 2 thus combines three closed entities and its skeleton SnO3InCl3NaO2Sn2O2 consists of three different metallic and two different non-metallic elements.

Biphasic solid state composites of the type metal/metal oxide or element/element oxide can be synthesized in one pot chemical reactions using so called molecular "single source precursors". Due to their singular genesis these composites show peculiar hetero-structures based on core-shell hierarchies such as superlattices and composite nanospheres or nanowires. They exhibit superior or new functional properties compared to their individual constituent compounds. In the current work, we review in particular the synthetical and mechanistical approach of bi-phasic (Al/Al2O3) nanostructures such as nanospheres, nanowires and nanoloops using a single source precursor. Other bi-phasic materials of the general formula M/MOx (for example M = Ge, Sn, Pb) are addressed for comparison. The impact of different synthetical conditions as well as of modification of surfaces by laser techniques and their technological relevance are presented briefly. Additionally, functional applications of the prepared surfaces are explained with some outstanding case studies. These case studies are primarily concerned with their use as biomaterials and their application in medicine as well as with their use as thin films for optics and functional surfaces.

Sol-gel coatings of tin doped indium oxide (ITO) were prepared via spin-coating, using a quasi single source precursor system that enhances homogeneous distribution of the dopant tin inside the oxide lattice. In addition, the implementation of metastable, bivalent tin into the gel layer enables the application of a one-step heat treatment under inert atmosphere, eliminating the need for the usually required critical post reduction treatment after crystallisation. The ITO layers produced were uniformly polycrystalline, with a homogeneous thickness of 60 nm. They showed increased electrical conductivity and optical performance in terms of transmission (vis) and IR reflection. The texture was less pronounced and the tensile residual stress determined in the layers was lower than in similar films, manufactured in a conventional two-step annealing process.

Treatment of diphenyl(3-thienyl)methanol HO–C(C16H13S) (1) with neodymium amide Nd[N(SiMe3)2]3 leads to Nd[OC(C16H13S)]3(thf)3} • thf (2). Single-crystal X-ray diffraction analysis of 2 reveals a mononuclear compound with an approximately octahedral geometry around the neodymium metal centre. The electrochemical investigations show that the cyclic voltammograms of 1 and 2 are only dominated by the oxidation of the thiophene moieties. Luminescence studies performed on 2 reveal the typical f-f transitions of the NdIII ion and exhibit an energy transfer from the ligand to the lanthanide ion.

Corundum (hexagonal) structure indium tin oxide (h-ITO) nanocrystals have been synthesized by subjecting an aqueous solution of In and Sn chlorides (Sn/In 8 wt.%) to a hydrothermal process followed by annealing at 450 °C in forming gas for 1 h. The annealing temperature was selected based on thermo-gravimetric analysis (TGA) and differential thermal analysis (DTA) of the dried precipitated powder, which showed a stable weight and phase at temperatures above 420 °C. X-ray diffraction (XRD) patterns showed the formation of orthorhombic InOOH precipitates that is transformed, after annealing, into h-ITO nanocrystals with 32 nm average crystal size. For nanostructure film deposition, dispersed sols of the prepared nanocrystals were spun coated on glass substrates. The films were densified by UV irradiation, whilst four-probe method was used to measure its sheet resistance. A sheet resistance as low as 10.6 kΩ □ have been reached. Scanning electron microscope (SEM) and high resolution transmission electron microscope (HRTEM) showed that the films have high surface roughness and nanopores. The transmittance spectra of the nanostructure films were measured in the UV-vis-NIR wavelength range. In addition to its low resistivity, nanostructure h-ITO films showed a wide range of transparency.

Novel organoplatinum(II) complexes with 2-acetylthiophene thiosemicarbazone (ATTSC) were synthesized. The reaction of K2PtCl4 with ATTSC in 1:1 and 1:2 metal to ligand ratios yielded 1 [Pt4(ATTSC-2H)4·4DMF] and 2 [Pt(ATTSC-H)(ATTSC)Cl·3CH3OH)]. The crystal structures of these platinum chelates have been solved by single-crystal X-ray diffraction structure determinations and revealed metalation of the thiophene ring at C2 through platinum atoms. Further characterization of 1 and 2 was performed using electronic, IR, UV/vis, and NMR spectroscopies and elemental analysis. The in vitro antitumor activity of the ligand as well as 1 and 2 was determined against two different human tumor cell lines (HT-29 and HuTu-80). These tests revealed that the platinum(II) complexes are more cytotoxic than their ligand. The tetranuclear complex 1 shows higher antiproliferative activity (IC50 = 1.2 and 1.5 µM) when compared to 2 (IC50 = 3 and 5.9 µM), while the ligand has IC50 values of 8.6 and >10 µM. Compounds 1 and 2 can therefore be considered as agents with potential antitumor activity.

This Letter is in response to a recent paper by Ma et al. (CrystEngComm, 2010, 12, 750-754) which arguably studied vanadium carbide nanostructures whereas all available evidence indicates the study of vanadium oxide. We feel that it is important to communicate to the community several inconsistencies so that the interesting material reported can be seen in the right light, especially with several groups nowadays having reported similar structures from vanadium oxide synthesis.

The effect of the micro- and nanotopography on vascular cell-surface interaction is investigated using nano- and microstructured Al2O3 as model substrate. Two different nanostructured Al2O3 surfaces composed of low density (LD) and high density (HD) nanowires (NWs) were synthesized by chemical vapour deposition (CVD) and commercially available microstructured Al2O3 plates were used for comparison. A clear diverging response of human umbilical vein endothelial cells (HUVEC) and human umbilical vein smooth muscle cells (HUVSMC) was observed on these nano- and microstructured surfaces. LD Al2O3 NWs seem to enhance the proliferation of HUVECs selectively. This selective control of the cell-surface interaction by topography may represent a key issue for the future stent material design.

Using the molecular compound Zr(OBut)4 in a liquid-injection chemical vapor deposition process, microporous zirconia membranes were deposited on porous multi-layered alumina substrates consisting of a macroporous α-alumina base covered with a mesoporous γ-alumina layer. The structure of nanocrystalline zirconia (ZrO2), membranes formed by the thermal decomposition of the precursor varied depending on the decomposition temperature and the injection frequency. The deposited zirconia membranes were characterized by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD) and atomic force microscopy (AFM). X-ray diffraction analysis patterns of the deposits obtained at 500 and 600 °C indicated a mixture of tetragonal and monoclinic ZrO2 phases, whereas the fraction of the monoclinic phase increased at higher substrate temperature and injection frequency. Morphology and surface roughness are strongly dependent on the process parameters. ZrO2 membranes prepared by the liquid-injection chemical vapor deposition had a microporous structure with less than 1 nm Kelvin diameter. The liquid-injection chemical vapor deposition is a unique method to prepare microporous membranes in one step without any post-treatment.

In this paper, we expressed murine gap junction protein Cx43 in Dictyostelium discoideum by introducing the specific vector pDXA. In the first step, the successful expression of Cx43 and Cx43-eGFP was verified by (a) Western blot (anti-Cx43, anti-GFP), (b) fluorescence microscopy (eGFP-Cx43 co-expression, Cx43 immunostaining), and (c) flow cytometry analysis (eGFP-Cx43 co-expression). Although the fluorescence signals from cells expressing Cx43-eGFP detected by fluorescence microscopy seem relatively low, analysis by flow cytometry demonstrated that more than 60% of cells expressed Cx43-eGFP. In order to evaluate the function of expressed Cx43 in D. discoideum, we examined the hemi-channel function of Cx43. In this series of experiments, the passive uptake of carboxyfluorescein was monitored using flow cytometric analysis. A significant number of the transfected cells showed a prominent dye uptake in the absence of Ca2+. The dye uptake by transfected cells in the presence of Ca2+ was even lower than the non-specific dye uptake by non-transformed Ax3 orf+ cells, confirming that Cx43 expressed in D. discoideum retains its Ca2+-dependent, specific gating function. The expression of gap junction proteins expressed in slime molds opens a possibility to the biological significance of intercellular communications in development and maintenance of multicellular organisms.