TY - BOOK A1 - Taubert, Andreas T1 - Ionische Flüssigkeiten : chemische Kuriosa oder sind sie doch recht nützlich? ; Antrittsvorlesung 2007-05-24 N2 - Klassischerweise haben Salze, beispielsweise Kochsalz, Schmelzpunkte von einigen hundert Grad Celsius und mehr. Ionische Flüssigkeiten sind dagegen Salze, deren Schmelzpunkt zum Teil weit unter der Raumtemperatur liegt. Sie sind daher bei Raumtemperatur flüssig. Obwohl ionische Flüssigkeiten seit 1914 bekannt sind, hatten sie bis vor 15 Jahren keinerlei Bedeutung. Heute jedoch werden ionische Flüssigkeiten aufgrund ihrer vorteilhaften Eigenschaften, wie hohe Leitfähigkeit oder hohe Temperaturstabilität, unter anderem zur Papierverarbeitung oder in flexiblen Solarzellen eingesetzt. Die Antrittsvorlesung wird sich insbesondere mit der Herstellung anorganischer Partikel befassen und zeigen, wie ionische Flüssigkeiten zur Herstellung neuer Materialien für verschiedene Anwendungen genutzt werden können. Y1 - 2007 UR - http://info.ub.uni-potsdam.de/multimedia/show_projekt.php?projekt_id=23 PB - Univ.-Bibl. CY - Potsdam ER - TY - JOUR A1 - Bleek, Katrin A1 - Taubert, Andreas T1 - New developments in polymer-controlled, bioinspired calcium phosphate mineralization from aqueous solution JF - Acta biomaterialia N2 - The polymer-controlled and bioinspired precipitation of inorganic minerals from aqueous solution at near-ambient or physiological conditions avoiding high temperatures or organic solvents is a key research area in materials science. Polymer-controlled mineralization has been studied as a model for biomineralization and for the synthesis of (bioinspired and biocompatible) hybrid materials for a virtually unlimited number of applications. Calcium phosphate mineralization is of particular interest for bone and dental repair. Numerous studies have therefore addressed the mineralization of calcium phosphate using a wide variety of low- and high-molecular-weight additives. In spite of the growing interest and increasing number of experimental and theoretical data, the mechanisms of polymer-controlled calcium phosphate mineralization are not entirely clear to date, although the field has made significant progress in the last years. A set of elegant experiments and calculations has shed light on some details of mineral formation, but it is currently not possible to preprogram a mineralization reaction to yield a desired product for a specific application. The current article therefore summarizes and discusses the influence of (macro)molecular entities such as polymers, peptides, proteins and gels on biomimetic calcium phosphate mineralization from aqueous solution. It focuses on strategies to tune the kinetics, morphologies, final dimensions and crystal phases of calcium phosphate, as well as on mechanistic considerations. KW - Calcium phosphate KW - Biomimetics KW - Mineralization KW - Polymers KW - Bioinspired Y1 - 2013 U6 - https://doi.org/10.1016/j.actbio.2012.12.027 SN - 1742-7061 SN - 1878-7568 VL - 9 IS - 5 SP - 6283 EP - 6321 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Shkilnyy, Andriy A1 - Brandt, Jessica A1 - Mantion, Alexandre A1 - Paris, Oskar A1 - Schlaad, Helmut A1 - Taubert, Andreas T1 - Calcium phosphate with a channel-like morphology by polymer templating N2 - Calcium phosphate mineralization from aqueous solution in the presence of organic growth modifiers has been intensely studied in the recent past. This is mostly due to potential applications of the resulting composites in the biomaterials field. Polymers in particular are efficient growth modifiers. As a result, there has been a large amount of work on polymeric growth modifiers. Interestingly, however, relatively little work has been done on polycationic additives. The current paper shows that poly(ethylene oxide)b-poly(L-lysine) block copolymers lead to an interesting morphology of calcium phosphate precipitated at room temperature and subjected to a mild heat treatment at 85 degrees C. Electron microscopy, synchrotron X-ray diffraction, and porosity analysis show that a (somewhat) porous material with channel-like features forms. Closer inspection using transmission electron microscopy shows that the channels are probably not real channels. Much rather the morphology is the result of the aggregation of ca. 100-nm-sized rodlike primary particles, which changes upon drying to exhibit the observed channel-like features. Comparison experiments conducted in the absence of polymer and with poly(ethylene oxide)-b-poly(L-glutamate) show that these features only form in the presence of the polycationic poly(L-lysine) block, suggesting a distinct interaction of the polycation with either the crystal or the phosphate ions prior to mineralization. Y1 - 2009 UR - http://pubs.acs.org/journal/cmatex U6 - https://doi.org/10.1021/Cm803244z SN - 0897-4756 ER - TY - JOUR A1 - Bagdahn, Christian A1 - Taubert, Andreas T1 - Ionogel fiber mats - functional materials via electrospinning of PMMA and the ionic liquid bis(1-butyl-3-methyl-imidazolium) Tetrachloridocuprate(II), [Bmim](2)[CuCl4] JF - Zeitschrift für Naturforschung : B, Chemical sciences N2 - Ionogel fiber mats were made by electrospinning poly(methylmethacrylate) (PMMA) and the ionic liquid (IL) bis(1-butyl-3-methyl-imidazolium) tetrachloridocupraten, [Bmim](2)[CuCl4], from acetone. The morphology of the electrospun ionogels strongly depends on the spinning parameters. Dense and uniform fiber mats were only obtained at concentrations of 60 to 70 g of polymer and IL mass combined. Lower concentrations led to a low number of poorly defined fibers. High voltages of 20 to 25 kV led to well-defined and uniform fibers; voltages between 15 and 20 kV again led to less uniform and less dense fibers. At 10 kV and lower, no spinning could be induced. Finally, PMMA fibers electrospun without IL show a less well-defined morphology combining fibers and oblong droplets indicating that the IL has a beneficial effect on the electrospinning process. The resulting materials are prototypes for new functional materials, for example in sterile filtration. KW - Ionic Liquid KW - Ionogel KW - Electrospinning KW - Fiber KW - Hydrogen Production KW - Filtration Y1 - 2013 U6 - https://doi.org/10.5560/ZNB.2013-3195 SN - 0932-0776 SN - 1865-7117 VL - 68 IS - 10 SP - 1163 EP - 1171 PB - De Gruyter CY - Tübingen ER - TY - JOUR A1 - Ayi, Ayi A. A1 - Khare, Varsha A1 - Strauch, Peter A1 - Girard, Jèrôme A1 - Fromm, Katharina M. A1 - Taubert, Andreas T1 - On the chemical synthesis of titanium nanoparticles from ionic liquids N2 - We report on attempts towards the synthesis of titanium nanoparticles using a wet chemical approach in imidazolium-based ionic liquids (ILs) under reducing conditions. Transmission electron microscopy finds nanoparticles in all cases. UV/Vis spectroscopy confirms the nanoparticulate nature of the precipitate, as in all cases an absorption band between ca. 280 and 300 nm is visible. IR spectroscopy shows that even after extensive washing and drying, some IL remains adsorbed on the nanoparticles. Raman spectroscopy suggests the formation of anatase nanoparticles, but X-ray diffraction reveals that, possibly, amorphous titania forms or that the nanoparticles are so small that a clear structure assignment is not possible. The report thus shows that (possibly amorphous) titanium oxides even form under reducing conditions and that the chemical synthesis of titanium nanoparticles in ILs remains elusive. Y1 - 2010 UR - http://www.springerlink.com/content/101572 U6 - https://doi.org/10.1007/s00706-010-0403-4 SN - 0026-9247 ER - TY - GEN A1 - Bleek, Katrin A1 - Taubert, Andreas T1 - New developments in polymer-controlled, bio-inspired calcium phosphate mineralization from aqueous solution T2 - Acta biomaterialia Y1 - 2013 U6 - https://doi.org/10.1016/j.actbio.2013.05.007 SN - 1742-7061 VL - 9 IS - 9 SP - 8466 EP - 8466 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Haase, Andrea A1 - Rott, Stephanie A1 - Mantion, Alexandre A1 - Graf, Philipp A1 - Plendl, Johanna A1 - Thünemann, Andreas F. A1 - Meier, Wolfgang P. A1 - Taubert, Andreas A1 - Luch, Andreas A1 - Reiser, Georg T1 - Effects of silver nanoparticles on primary mixed neural cell cultures: Uptake, oxidative stress and acute calcium responses JF - Toxicological sciences N2 - In the body, nanoparticles can be systemically distributed and then may affect secondary target organs, such as the central nervous system (CNS). Putative adverse effects on the CNS are rarely investigated to date. Here, we used a mixed primary cell model consisting mainly of neurons and astrocytes and a minor proportion of oligodendrocytes to analyze the effects of well-characterized 20 and 40 nm silver nanoparticles (SNP). Similar gold nanoparticles served as control and proved inert for all endpoints tested. SNP induced a strong size-dependent cytotoxicity. Additionally, in the low concentration range (up to 10 mu g/ml of SNP), the further differentiated cultures were more sensitive to SNP treatment. For detailed studies, we used low/medium dose concentrations (up to 20 mu g/ml) and found strong oxidative stress responses. Reactive oxygen species (ROS) were detected along with the formation of protein carbonyls and the induction of heme oxygenase-1. We observed an acute calcium response, which clearly preceded oxidative stress responses. ROS formation was reduced by antioxidants, whereas the calcium response could not be alleviated by antioxidants. Finally, we looked into the responses of neurons and astrocytes separately. Astrocytes were much more vulnerable to SNP treatment compared with neurons. Consistently, SNP were mainly taken up by astrocytes and not by neurons. Immunofluorescence studies of mixed cell cultures indicated stronger effects on astrocyte morphology. Altogether, we can demonstrate strong effects of SNP associated with calcium dysregulation and ROS formation in primary neural cells, which were detectable already at moderate dosages. KW - silver nanoparticles KW - neurons KW - oxidative stress KW - protein carbonyls KW - calcium Y1 - 2012 U6 - https://doi.org/10.1093/toxsci/kfs003 SN - 1096-6080 VL - 126 IS - 2 SP - 457 EP - 468 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Haase, A. A1 - Mantion, A. A1 - Graf, P. A1 - Plendl, J. A1 - Thünemann, Andreas F. A1 - Meier, Wolfgang P. A1 - Taubert, Andreas A1 - Luch, A. T1 - A novel type of silver nanoparticles and their advantages in toxicity testing in cell culture systems JF - Archives of toxicology : official journal of EUROTOX N2 - Silver nanoparticles (SNPs) are among the most commercialized nanoparticles worldwide. Often SNP are used because of their antibacterial properties. Besides that they possess unique optic and catalytic features, making them highly interesting for the creation of novel and advanced functional materials. Despite its widespread use only little data exist in terms of possible adverse effects of SNP on human health. Conventional synthesis routes usually yield products of varying quality and property. It thus may become puzzling to compare biological data from different studies due to the great variety in sizes, coatings or shapes of the particles applied. Here, we applied a novel synthesis approach to obtain SNP of well-defined colloidal and structural properties. Being stabilized by a covalently linked small peptide, these particles are nicely homogenous, with narrow size distribution, and form monodisperse suspensions in aqueous solutions. We applied these peptide-coated SNP in two different sizes of 20 or 40 nm (Ag20Pep and Ag40Pep) and analyzed responses of THP-1-derived human macrophages while being exposed against these particles. Gold nanoparticles of similar size and coating (Au20Pep) were used for comparison. The cytotoxicity of particles was assessed by WST-1 and LDH assays, and the uptake into the cells was confirmed via transmission electron microscopy. In summary, our data demonstrate that this novel type of SNP is well suited to serve as model system for nanoparticles to be tested in toxicological studies in vitro. KW - Silver nanoparticles KW - Peptide coating KW - Nanotoxicity Y1 - 2012 U6 - https://doi.org/10.1007/s00204-012-0836-0 SN - 0340-5761 VL - 86 IS - 7 SP - 1089 EP - 1098 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Tentschert, J. A1 - Draude, F. A1 - Jungnickel, H. A1 - Haase, A. A1 - Mantion, Alexandre A1 - Galla, S. A1 - Thuenemann, Andreas F. A1 - Taubert, Andreas A1 - Luch, A. A1 - Arlinghaus, H. F. T1 - TOF-SIMS analysis of cell membrane changes in functional impaired human macrophages upon nanosilver treatment JF - Surface and interface analysis : an international journal devoted to the development and application of techniques for the analysis surfaces, interfaces and thin films N2 - Silver nanoparticles (SNP) are among the most commercialized nanoparticles. Here, we show that peptide-coated SNP cause functional impairment of human macrophages. A dose-dependent inhibition of phagocytosis is observed after nanoparticle treatment, and pretreatment of cells with N-acetyl cysteine (NAC) can counteract the phagocytosis disturbances caused by SNP. Using the surface-sensitive mode of time-of-flight secondary ion mass spectrometry, in combination with multivariate statistical methods, we studied the composition of cell membranes in human macrophages upon exposure to SNP with and without NAC preconditioning. This method revealed characteristic changes in the lipid pattern of the cellular membrane outer leaflet in those cells challenged by SNP. Statistical analyses resulted in 19 characteristic ions, which can be used to distinguish between NAC pretreated and untreated macrophages. The present study discusses the assignments of surface cell membrane phospholipids for the identified ions and the resulting changes in the phospholipid pattern of treated cells. We conclude that the adverse effects in human macrophages caused by SNP can be partially reversed through NAC administration. Some alterations, however, remained. KW - silver nanoparticles KW - lipidomics KW - N-acetyl cysteine KW - phagocytosis KW - oxidative stress Y1 - 2013 U6 - https://doi.org/10.1002/sia.5155 SN - 0142-2421 VL - 45 IS - 1 SP - 483 EP - 485 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Casse, Olivier A1 - Shkilnyy, Andriy A1 - Linders, Jürgen A1 - Mayer, Christian A1 - Häussinger, Daniel A1 - Völkel, Antje A1 - Thünemann, Andreas F. A1 - Dimova, Rumiana A1 - Cölfen, Helmut A1 - Meier, Wolfgang P. A1 - Schlaad, Helmut A1 - Taubert, Andreas T1 - Solution behavior of double-hydrophilic block copolymers in dilute aqueous solution JF - Macromolecules : a publication of the American Chemical Society N2 - The self-assembly of double-hydrophilic poly(ethylene oxide)-poly(2-methyl-2-oxazoline) diblock copolymers in water has been studied. Isothermal titration calorimetry, small-angle X-ray scattering, and analytical ultracentrifugation suggest that only single polymer chains are present in solution. In contrast, light scattering and transmission electron microscopy detect aggregates with radii of ca. 100 nm. Pulsed field gradient NMR spectroscopy confirms the presence of aggregates, although only 2% of the polymer chains undergo aggregation. Water uptake experiments indicate differences in the hydrophilicity of the two blocks, which is believed to be the origin of the unexpected aggregation behavior (in accordance with an earlier study by Ke et al. [Macromolecules 2009, 42, 5339-5344]). The data therefore suggest that even in double-hydrophilic block copolymers, differences in hydrophilicity are sufficient to drive polymer aggregation, a phenomenon that has largely been overlooked or ignored so far. Y1 - 2012 U6 - https://doi.org/10.1021/ma300621g SN - 0024-9297 VL - 45 IS - 11 SP - 4772 EP - 4777 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Ziolkowski, Bartosz A1 - Bleek, Katrin A1 - Twamley, Brendan A1 - Fraser, Kevin J. A1 - Byrne, Robert A1 - Diamond, Dermot A1 - Taubert, Andreas T1 - Magnetic ionogels (MagIGs) based on iron oxide nanoparticles, poly(N-isopropylacrylamide), and the ionic liquid trihexyl(tetradecyl)phosphonium dicyanamide JF - European journal of inorganic chemistry : a journal of ChemPubSoc Europe N2 - Magnetic ionogels (MagIGs) were prepared from organosilane-coated iron oxide nanoparticles, N-isopropylacrylamide, and the ionic liquid trihexyl(tetradecyl)phosphonium dicyanamide. The ionogels prepared with the silane-modified nanoparticles are more homogeneous than ionogels prepared with unmodified magnetite particles. The silane-modified particles are immobilized in the ionogel and are resistant tonanoparticle leaching. The modified particles also render the ionogels mechanically more stable than the ionogels synthesized with unmodified nanoparticles. The ionogels respond to external permanent magnets and are therefore prototypes of a new soft magnetic actuator. KW - Magnetic properties KW - Nanotechnology KW - Iron KW - Ionic liquids KW - Ionogels Y1 - 2012 U6 - https://doi.org/10.1002/ejic.201200597 SN - 1434-1948 IS - 32 SP - 5245 EP - 5251 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Junginger, Mathias A1 - Kübel, Christian A1 - Schacher, Felix H. A1 - Müller, Axel H. E. A1 - Taubert, Andreas T1 - Crystal structure and chemical composition of biomimetic calcium phosphate nanofibers JF - RSC Advances N2 - Calcium phosphate nanofibers with a diameter of only a few nanometers and a cotton-ball-like aggregate morphology have been reported several times in the literature. Although fiber formation seems reproducible in a variety of conditions, the crystal structure and chemical composition of the fibers have been elusive. Using scanning transmission electron microscopy, low dose electron (nano) diffraction, energy-dispersive X-ray spectroscopy, and energy-filtered transmission electron microscopy, we have assigned crystal structures and chemical compositions to the fibers. Moreover, we demonstrate that the mineralization process yields true polymer/calcium phosphate hybrid materials where the block copolymer template is closely associated with the calcium phosphate. Y1 - 2013 U6 - https://doi.org/10.1039/c3ra23348k SN - 2046-2069 VL - 3 IS - 28 SP - 11301 EP - 11308 PB - Royal Society of Chemistry CY - Cambridge ER - TY - INPR A1 - Bühler, Markus J. A1 - Rabu, Pierre A1 - Taubert, Andreas T1 - Advanced hybrid materials - design and applications T2 - European journal of inorganic chemistry : a journal of ChemPubSoc Europe Y1 - 2012 U6 - https://doi.org/10.1002/ejic.201201263 SN - 1434-1948 IS - 32 SP - 5092 EP - 5093 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Xie, Zai-Lai A1 - Xu, Hai-Bing A1 - Gessner, Andre A1 - Kumke, Michael Uwe A1 - Priebe, Magdalena A1 - Fromm, Katharina M. A1 - Taubert, Andreas T1 - A transparent, flexible, ion conductive, and luminescent PMMA ionogel based on a Pt/Eu bimetallic complex and the ionic liquid [Bmim][N(Tf)(2)] JF - Journal of materials chemistry N2 - Transparent, ion-conducting, luminescent, and flexible ionogels based on the room temperature ionic liquid (IL) 1-butyl-3-methylimidazolium bis(trifluoromethane sulfonyl) imide [Bmim][N(Tf)(2)], a PtEu2 chromophore, and poly(methylmethacrylate) (PMMA) have been prepared. The thermal stability of the PMMA significantly increases with IL incorporation. In particular, the onset weight loss observed at ca. 229 degrees C for pure PMMA increases to 305 degrees C with IL addition. The ionogel has a high ionic conductivity of 10(-3) S cm(-1) at 373 K and exhibits a strong emission in the red with a long average luminescence decay time of tau = 890 mu s. The resulting material is a new type of soft hybrid material featuring useful thermal, optical, and ion transport properties. Y1 - 2012 U6 - https://doi.org/10.1039/c2jm15862k SN - 0959-9428 VL - 22 IS - 16 SP - 8110 EP - 8116 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Si, Satyabrata A1 - Taubert, Andreas A1 - Mantion, Alexandre A1 - Rogez, Guillaume A1 - Rabu, Pierre T1 - Peptide-intercalated layered metal hydroxides effect of peptide chain length and side chain functionality on structural, optical and magnetic properties JF - Chemical science N2 - New hybrid materials have been prepared by grafting synthetic peptides in the interlayer spacing of Cu(II) and Co(II) layered simple hydroxides (LSHs). The interlayer spacing of the hybrids depends on the peptide chain length; the dependence is specific for the copper and cobalt-based hybrids. This suggests a metal-or LSH-specific interaction of the peptides with the respective inorganic layers. When tyrosine is present in the peptide, its fluorescence is quenched after grafting the peptide to the LSH. Studies of the luminescence vs. pH indicate deprotonation of the tyrosine moieties to tyrosinate at high pH, accompanied by the onset of luminescence. The luminescence increases with increasing OH- concentration, suggesting an application of the hybrids as chemical sensors. Moreover, the peptides influence the magnetic properties of the hybrids. The copper-based hybrids behave antiferromagnetically and the cobalt-based hybrids are ferrimagnets. Y1 - 2012 U6 - https://doi.org/10.1039/c2sc01087a SN - 2041-6520 VL - 3 IS - 6 SP - 1945 EP - 1957 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Delahaye, Emilie A1 - Goebel, Ronald A1 - Loebbicke, Ruben A1 - Guillot, Regis A1 - Sieber, Christoph A1 - Taubert, Andreas T1 - Silica ionogels for proton transport JF - Journal of materials chemistry N2 - A number of ionogels - silica-ionic liquid (IL) hybrid materials - were synthesized and studied for their ionic conductivity. The materials are based on a sulfonated IL, 1-methyl-3-(3-sulfopropyl-)-imidazolium p-toluenesulfonate, [PmimSO(3)H][PTS], which contains a sulfonic acid/sulfonate group both in the IL anion and in the side chain of the IL cation. By way of the sulfonate-sulfonic acid proton transfer, the IL imparts the ionogel with a high ionic conductivity of ca. 10(-2) S cm(-1) in the as-synthesized state at 120 degrees C and 10(-3) S cm(-1) in the dry state at 120 degrees C. The ionogels are stable up to ca. 150 degrees C in dynamic thermogravimetric analysis. This suggests that these materials, which are relatively cheap and easily fabricated, could find application in fuel cells in intermediate temperature ranges where many other membrane materials are not suitable. Y1 - 2012 U6 - https://doi.org/10.1039/c2jm00037g SN - 0959-9428 VL - 22 IS - 33 SP - 17140 EP - 17146 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Goebel, Ronald A1 - White, Robin J. A1 - Titirici, Maria-Magdalena A1 - Taubert, Andreas T1 - Carbon-based ionogels tuning the properties of the ionic liquid via carbon-ionic liquid interaction JF - Physical chemistry, chemical physics : a journal of European Chemical Societies N2 - The behavior of two ionic liquids (ILs), 1-ethyl-3-methylimidazolium dicyanamide [Emim][DCA] and 1-ethyl-3-methylimidazolium triflate [Emim][TfO], in (meso) porous carbonaceous hosts was investigated. Prior to IL incorporation into the host, the carbon matrix was thermally annealed between 180 and 900 degrees C to control carbon condensation and surface chemistry. The resulting materials have an increasing "graphitic'' carbon character with increasing treatment temperature, reflected in a modified behavior of the ILs when impregnated into the carbon host. The two ILs show significant changes in the thermal behavior as measured from differential scanning calorimetry; these changes can be assigned to anion-pi interaction between the IL anions and the pore wall surfaces of these flexible carbonaceous support materials. Y1 - 2012 U6 - https://doi.org/10.1039/c2cp23929a SN - 1463-9076 VL - 14 IS - 17 SP - 5992 EP - 5997 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Neumann, Mike A1 - Noeske, Robert A1 - Taubert, Andreas A1 - Tiersch, Brigitte A1 - Strauch, Peter T1 - Highly structured, biomorphous beta-SiC with high specific surface area from Equisetaceae JF - Journal of materials chemistry N2 - Mesoporous, highly structured silicon carbide (beta-SiC) was synthesised from renewable plant materials (two Equisetaceae species) in a one-step carbothermal process at remarkably low temperatures down to 1200 degrees C. The SiC precursor is a silicon-carbon mixture with finely dispersed carbon prepared by pyrolysis of the organic plant matrix. Yields are 3 to 100% (omega(Si/Si) related to the silicon deposited in the plant material), depending on reaction temperature and time. IR spectroscopy, X-ray diffraction, and nitrogen sorption prove the formation of high-purity beta-SiC with minor inorganic impurities after purification and a high specific surface area of up to 660 m(2) g(-1). Scanning electron microscopy shows that the plant morphology is maintained in the final SiC. Sedimentation analysis finds a mean particle size (diameters d(50)) of 20 mu m. Y1 - 2012 U6 - https://doi.org/10.1039/c2jm30253e SN - 0959-9428 VL - 22 IS - 18 SP - 9046 EP - 9051 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Yuan, Jiayin A1 - ten Brummelhuis, Niels A1 - Junginger, Mathias A1 - Xie, Zailai A1 - Lu, Yan A1 - Taubert, Andreas A1 - Schlaad, Helmut T1 - Diversified applications of chemically modified 1,2-Polybutadiene JF - Macromolecular rapid communications N2 - Commercially available 1,2-PB was transformed into a well-defined reactive intermediate by quantitative bromination. The brominated polymer was used as a polyfunctional macroinitiator for the cationic ring-opening polymerization of 2-ethyl-2-oxazoline to yield a water-soluble brush polymer. Nucleophilic substitution of bromide by 1-methyl imidazole resulted in the formation of polyelectrolyte copolymers consisting of mixed units of imidazolium, bromo, and double bond. These copolymers, which were soluble in water without forming aggregates, were used as stabilizers in the heterophase polymerization of styrene and were also studied for their ionic conducting properties. KW - emulsion polymerization KW - polybutadiene KW - polyelectrolytes KW - polymer modification KW - ring-opening polymerization Y1 - 2011 U6 - https://doi.org/10.1002/marc.201100254 SN - 1022-1336 VL - 32 IS - 15 SP - 1157 EP - 1162 PB - Wiley-Blackwell CY - Malden ER - TY - JOUR A1 - Haase, Andrea A1 - Arlinghaus, Heinrich F. A1 - Tentschert, Jutta A1 - Jungnickel, Harald A1 - Graf, Philipp A1 - Mantion, Alexandre A1 - Draude, Felix A1 - Galla, Sebastian A1 - Plendl, Johanna A1 - Goetz, Mario E. A1 - Masic, Admir A1 - Meier, Wolfgang P. A1 - Thuenemann, Andreas F. A1 - Taubert, Andreas A1 - Luch, Andreas T1 - Application of Laser Postionization Secondary Neutral Mass Spectrometry/Time-of-Flight Secondary Ion Mass Spectrometry in Nanotoxicology: Visualization of Nanosilver in Human Macrophages and Cellular Responses JF - ACS nano N2 - Silver nanoparticles (SNP) are the subject of worldwide commercialization because of their antimicrobial effects. Yet only little data on their mode of action exist. Further, only few techniques allow for visualization and quantification of unlabeled nanoparticles inside cells. To study SNP of different sizes and coatings within human macrophages, we introduce a novel laser postionization secondary neutral mass spectrometry (Laser-SNMS) approach and prove this method superior to the widely applied confocal Raman and transmission electron microscopy. With time-of-flight secondary ion mass spectrometry (TOF-SIMS) we further demonstrate characteristic fingerprints in the lipid pattern of the cellular membrane indicative of oxidative stress and membrane fluidity changes. Increases of protein carbonyl and heme oxygenase-1 levels in treated cells confirm the presence of oxidative stress biochemically. Intriguingly, affected phagocytosis reveals as highly sensitive end point of SNP-mediated adversity In macrophages. The cellular responses monitored are. hierarchically linked, but follow individual kinetics and are partially reversible. KW - nanosilver KW - Laser-SNMS KW - TOF-SIMS KW - confocal Raman microscopy KW - oxidative stress KW - protein carbonyls Y1 - 2011 U6 - https://doi.org/10.1021/nn200163w SN - 1936-0851 VL - 5 IS - 4 SP - 3059 EP - 3068 PB - American Chemical Society CY - Washington ER -