TY  - JOUR
A1  - Goebel, Ronald
A1  - Hesemann, Peter
A1  - Weber, Jens
A1  - Moeller, Eléonore
A1  - Friedrich, Alwin
A1  - Beuermann, Sabine
A1  - Taubert, Andreas
T1  - Surprisingly high, bulk liquid-like mobility of silica-confined ionic liquids
N2  - Mesoporous silica monoliths were prepared by the sol - gel technique and. lled with 1-ethyl-3-methyl imidazolium [Emim]-X (X = dicyanamide [N(CN)(2)], ethyl sulfate [EtSO4], thiocyanate [SCN], and triflate [TfO]) ionic liquids (ILs) using a methanol-IL exchange technique. The structure and behavior of the ILs inside the silica monoliths were studied using X-ray scattering, nitrogen sorption, IR spectroscopy, solid-state NMR, and thermal analysis. DSC finds shifts in both the glass transition temperature and melting points (where applicable) of the ILs. Glass transition and melting occur well below room temperature. There is thus no conflict with the NMR and IR data, which show that the ILs are as mobile at room temperature as the bulk (not confined) ILs. The very narrow line widths of the NMR spectra suggest that the ILs in our materials have the highest mobility reported for confined ILs so far. As a result, our data suggest that it is possible to generate IL/silica hybrid materials (ionogels) with bulk-like properties of the IL. This could be interesting for applications in, e.g., the solar cell or membrane fields.
Y1  - 2009
UR  - http://xlink.rsc.org/jumptojournal.cfm?journal_code=CP
U6  - https://doi.org/10.1039/B821833a
SN  - 1463-9076
ER  - 
TY  - JOUR
A1  - Kind, Lucy
A1  - Plamper, Felix A.
A1  - Goebel, Ronald
A1  - Mantion, Alexandre
A1  - Mueller, Axel H. E.
A1  - Pieles, Uwe
A1  - Taubert, Andreas
A1  - Meier, Wolfgang P.
T1  - Silsesquioxane/polyamine nanoparticle-templated formation of star- or raspberry-like silica nanoparticles
N2  - Silica is an important mineral in biology and technology, and many protocols have been developed for the synthesis of complex silica architectures. The current report shows that silsesquioxane nanoparticles carrying polymer arms on their surface are efficient templates for the fabrication of silica particles with a star- or raspberry-like morphology. The shape of the resulting particles depends on the chemistry of the polymer arms. With poly(N,N- dimethylaminoethyl methacrylate) (PDMAEMA) arms, spherical particles with a less electron dense core form. With poly {[2- (methacryloyloxy)ethyl] trimethylammonium iodide} (PMETAI), star- or raspberry-like particles form. Electron microscopy, electron tomography, and small-angle X-ray scattering show that the resulting silica particles have a complex structure, where a silsequioxane nanoparticle carrying the polymer arms is in the center. Next is a region that is polymer-rich. The outermost region of the particle is a silica layer, where the outer parts of the polymer arms are embedded. Time- resolved zeta-potential and pH measurements, dynamic light scattering, and electron microscopy reveal that silica formation proceeds differently if PDMAEMA is exchanged for PMETAI.
Y1  - 2009
UR  - http://pubs.acs.org/journal/langd5
U6  - https://doi.org/10.1021/La900229n
SN  - 0743-7463
ER  - 
TY  - JOUR
A1  - Graf, Philipp
A1  - Mantion, Alexandre
A1  - Foelske, Annette
A1  - Shkilnyy, Andriy
A1  - MaÜic, Admir
A1  - Thuenemann, Andreas F.
A1  - Taubert, Andreas
T1  - Peptide-coated silver nanoparticles : synthesis, surface chemistry, and pH-triggered, reversible assembly into particle assemblies
N2  - Simple tripeptides are scaffolds for the synthesis and further assembly of peptide/silver nanoparticle composites. Herein, we further explore peptide-con trolled silver nanoparticle assembly processes. Silver nanoparticles with a pH-responsive peptide coating have been synthesized by using a one-step precipitation/coating route. The nature of the peptide/silver interaction and the effect of the peptide oil the formation of the silver particles have been studied via UV/Vis, X-ray photoelectron, and surface-enhanced Raman spectroscopies as well as through electron microscopy, small angle X-ray scattering and powder Xray diffraction with Rietveld refinement. The particles reversibly form aggregates of different sizes in aqueous solution. The state of aggregation call be controlled by the solution pH value. At low pH values, individual particles are present. At neutral pH values, small clusters form and at high pH values, large precipitates are observed.
Y1  - 2009
UR  - http://www3.interscience.wiley.com/cgi-bin/jhome/26293/
U6  - https://doi.org/10.1002/chem.200802329
SN  - 0947-6539
ER  - 
TY  - JOUR
A1  - Navarro, Salvador
A1  - Shkilnyy, Andriy
A1  - Tiersch, Brigitte
A1  - Taubert, Andreas
A1  - Menzel, Henning
T1  - Preparation, characterization, and thermal gelation of amphiphilic alkyl-poly(ethyleneimine)
N2  - Amphiphilic alkyl-poly(ethyleneimine)s (alkyl-PEI) with different degrees of polymerization have been produced by alkaline hydrolysis of alkyl-poly(2-methyl-2-oxazoline). Potentiometric titration of the alkyl-PEI shows the influence of the alkyl chain and the degree of polymerization on the titration curves and hence on the polymer conformation. Karl Fischer titration has been used to determine the water content in the polymers. Subsequent X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC) measurements prove the existence of different hydration states of the PEI even under dry storage conditions. Upon cooling from hot aqueous Solutions, hydrogels form. The gelation concentration decreases with increasing degree of polymerization of the PEI segment. Scanning electron microscopy (SEM and cryo-SEM) of the hydrogels reveal an alkyl-PEI fibrous network composed of fan-like units. DSC shows that the percentages of bound and free water in the hydrogels depend on the concentration of polar amino groups.
Y1  - 2009
UR  - http://pubs.acs.org/journal/langd5
U6  - https://doi.org/10.1021/La9013569
SN  - 0743-7463
ER  - 
TY  - JOUR
A1  - Schweizer, S.
A1  - Schuster, T.
A1  - Junginger, Matthias
A1  - Siekmeyer, Gerd
A1  - Taubert, Andreas
T1  - Surface modification of ickel/Titanium Alloy and Titanium Surfaces via a Polyelectrolyte Multilayer/Calcium Phosphate Hybrid Coating
N2  - The report shows that simple LbL deposition of positively charged chitosan and negatively charged heparin can be used to efficiently modify the native surface of both NiTi and Ti without any previous treatments. Moreover, mineralization of the polymer multilayers with calcium phosphate leads to surfaces with low contact angles around 70 and 20 degrees for NiTi and Ti, respectively. This suggests that a polymer multilayer/calcium phosphate hybrid coating could be useful for making NiTi or Ti implants that are at the same time antibacterial (via the chitosan), suppress blood clot formation (via the heparin), and favor fast endothelialization (via the improved surface hydrophilicity compared to the respective neat material).
Y1  - 2010
UR  - http://onlinelibrary.wiley.com/doi/10.1002/mame.200900347/pdf
U6  - https://doi.org/10.1002/mame.200900347
SN  - 1438-7492
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  - 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  - 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  -