Dokument-ID Dokumenttyp Verfasser/Autoren Herausgeber Haupttitel Abstract Auflage Verlagsort Verlag Erscheinungsjahr Seitenzahl Schriftenreihe Titel Schriftenreihe Bandzahl ISBN Quelle der Hochschulschrift Konferenzname Quelle:Titel Quelle:Jahrgang Quelle:Heftnummer Quelle:Erste Seite Quelle:Letzte Seite URN DOI Abteilungen OPUS4-39308 Wissenschaftlicher Artikel Hentrich, Doreen; Junginger, Mathias; Bruns, Michael; Boerner, Hans G.; Brandt, Jessica; Brezesinski, Gerald; Taubert, Andreas Interface-controlled calcium phosphate mineralization: effect of oligo(aspartic acid)-rich interfaces The phase behavior of an amphiphilic block copolymer based on a poly(aspartic acid) hydrophilic block and a poly(n-butyl acrylate) hydrophobic block was investigated at the air-water and air-buffer interface. The polymer forms stable monomolecular films on both subphases. At low pH, the isotherms exhibit a plateau. Compression-expansion experiments and infrared reflection absorption spectroscopy suggest that the plateau is likely due to the formation of polymer bi- or multilayers. At high pH the films remain intact upon compression and no multilayer formation is observed. Furthermore, the mineralization of calcium phosphate beneath the monolayer was studied at different pH. The pH of the subphase and thus the polymer charge strongly affects the phase behavior of the film and the mineral formation. After 4 h of mineralization at low pH, atomic force microscopy shows smooth mineral films with a low roughness. With increasing pH the mineral films become inhomogeneous and the roughness increases. Transmission electron microscopy confirms this: at low pH a few small but uniform particles form whereas particles grown at higher pH are larger and highly agglomerated. Energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy confirm the formation of calcium phosphate. The levels of mineralization are higher in samples grown at high pH. Cambridge Royal Society of Chemistry 2015 13 CrystEngComm 17 36 6901 6913 10.1039/c4ce02274b Institut für Chemie OPUS4-8953 Wissenschaftlicher Artikel Hentrich, Doreen; Junginger, Mathias; Bruns, Michael; Börner, Hans Gerhard; Brandt, Jessica; Brezesinski, Gerald; Taubert, Andreas Interface-controlled calcium phosphate mineralization The phase behavior of an amphiphilic block copolymer based on a poly(aspartic acid) hydrophilic block and a poly(n-butyl acrylate) hydrophobic block was investigated at the air-water and air-buffer interface. The polymer forms stable monomolecular films on both subphases. At low pH, the isotherms exhibit a plateau. Compression-expansion experiments and infrared reflection absorption spectroscopy suggest that the plateau is likely due to the formation of polymer bi- or multilayers. At high pH the films remain intact upon compression and no multilayer formation is observed. Furthermore, the mineralization of calcium phosphate beneath the monolayer was studied at different pH. The pH of the subphase and thus the polymer charge strongly affects the phase behavior of the film and the mineral formation. After 4 h of mineralization at low pH, atomic force microscopy shows smooth mineral films with a low roughness. With increasing pH the mineral films become inhomogeneous and the roughness increases. Transmission electron microscopy confirms this: at low pH a few small but uniform particles form whereas particles grown at higher pH are larger and highly agglomerated. Energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy confirm the formation of calcium phosphate. The levels of mineralization are higher in samples grown at high pH. London Royal Society of Chemistry 2015 12 CrystEngComm 17 6901 6913 10.1039/C4CE02274B Institut für Chemie OPUS4-39328 Wissenschaftlicher Artikel Kirchhecker, Sarah; Tröger-Müller, Steffen; Bake, Sebastian; Antonietti, Markus; Taubert, Andreas; Esposito, Davide Renewable pyridinium ionic liquids from the continuous hydrothermal decarboxylation of furfural-amino acid derived pyridinium zwitterions Fully renewable pyridinium ionic liquids were synthesised via the hydrothermal decarboxylation of pyridinium zwitterions derived from furfural and amino acids in flow. The functionality of the resulting ionic liquid (IL) can be tuned by choice of different amino acids as well as different natural carboxylic acids as the counter-ions. A representative member of this new class of ionic liquids was successfully used for the synthesis of ionogels and as a solvent for the Heck coupling. Cambridge Royal Society of Chemistry 2015 6 Green chemistry : an international journal and green chemistry resource 17 8 4151 4156 10.1039/c5gc00913h Institut für Chemie OPUS4-8138 Wissenschaftlicher Artikel Kirchhecker, Sarah; Tröger-Müller, Steffen; Bake, Sebastian; Antonietti, Markus; Taubert, Andreas; Esposito, Davido Renewable pyridinium ionic liquids from the continuous hydrothermal decarboxylation of furfural-amino acid derived pyridinium zwitterions Fully renewable pyridinium ionic liquids were synthesised via the hydrothermal decarboxylation of pyridinium zwitterions derived from furfural and amino acids in flow. The functionality of the resulting ionic liquid (IL) can be tuned by choice of different amino acids as well as different natural carboxylic acids as the counterions. A representative member of this new class of ionic liquids was successfully used for the synthesis of ionogels and as a solvent for the Heck coupling. Cambridge Royal Society of Chemistry 2015 5 Green chemistry 8 17 4151 4156 10.1039/c5gc00913h Institut für Chemie OPUS4-39117 Wissenschaftlicher Artikel Leroux, Fabrice; Rabu, Pierre; Sommerdijk, Nico A. J. M.; Taubert, Andreas Two-Dimensional Hybrid Materials: Transferring Technology from Biology to Society Hybrid materials are at the forefront of modern research and technology; hence a large number of publications on hybrid materials has already appeared in the scientific literature. This essay focuses on the specifics and peculiarities of hybrid materials based on two-dimensional (2D) building blocks and confinements, for two reasons: (1) 2D materials have a very broad field of application, but they also illustrate many of the scientific challenges the community faces, both on a fundamental and an application level; (2) all authors of this essay are involved in research on 2D materials, but their perspective and vision of how the field will develop in the future and how it is possible to benefit from these new developments are rooted in very different scientific subfields. The current article will thus present a personal, yet quite broad, account of how hybrid materials, specifically 2D hybrid materials, will provide means to aid modern societies in fields as different as healthcare and energy. Weinheim Wiley-VCH 2015 7 European journal of inorganic chemistry : a journal of ChemPubSoc Europe 7 1089 1095 10.1002/ejic.201500153 Institut für Chemie OPUS4-39267 Wissenschaftlicher Artikel Mai, Tobias; Boye, Susanne; Yuan, Jiayin; Voelkel, Antje; Graewert, Marlies; Günter, Christina; Lederer, Albena; Taubert, Andreas Poly(ethylene oxide)-based block copolymers with very high molecular weights for biomimetic calcium phosphate mineralization The present article is among the first reports on the effects of poly(ampholyte)s and poly(betaine) s on the biomimetic formation of calcium phosphate. We have synthesized a series of di- and triblock copolymers based on a non-ionic poly(ethylene oxide) block and several charged methacrylate monomers, 2-(trimethylammonium) ethyl methacrylate chloride, 2-((3-cyanopropyl)-dimethylammonium)ethyl methacrylate chloride, 3-sulfopropyl methacrylate potassium salt, and [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) ammonium hydroxide. The resulting copolymers are either positively charged, ampholytic, or betaine block copolymers. All the polymers have very high molecular weights of over 10(6) g mol(-1). All polymers are water-soluble and show a strong effect on the precipitation and dissolution of calcium phosphate. The strongest effects are observed with triblock copolymers based on a large poly(ethylene oxide) middle block (nominal M-n = 100 000 g mol(-1)). Surprisingly, the data show that there is a need for positive charges in the polymers to exert tight control over mineralization and dissolution, but that the exact position of the charge in the polymer is of minor importance for both calcium phosphate precipitation and dissolution. Cambridge Royal Society of Chemistry 2015 12 RSC Advances 5 125 103494 103505 10.1039/c5ra20035k Institut für Chemie OPUS4-8528 Wissenschaftlicher Artikel Mai, Tobias; Boye, Susanne; Yuan, Jiayin; Völkel, Antje; Gräwert, Marlies; Günter, Christina; Lederer, Albena; Taubert, Andreas Poly(ethylene oxide)-based block copolymers with very high molecular weights for biomimetic calcium phosphate mineralization The present article is among the first reports on the effects of poly(ampholyte)s and poly(betaine)s on the biomimetic formation of calcium phosphate. We have synthesized a series of di- and triblock copolymers based on a non-ionic poly(ethylene oxide) block and several charged methacrylate monomers, 2-(trimethylammonium)ethyl methacrylate chloride, 2-((3-cyanopropyl)-dimethylammonium)ethyl methacrylate chloride, 3-sulfopropyl methacrylate potassium salt, and [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide. The resulting copolymers are either positively charged, ampholytic, or betaine block copolymers. All the polymers have very high molecular weights of over 106 g mol−1. All polymers are water-soluble and show a strong effect on the precipitation and dissolution of calcium phosphate. The strongest effects are observed with triblock copolymers based on a large poly(ethylene oxide) middle block (nominal Mn = 100 000 g mol−1). Surprisingly, the data show that there is a need for positive charges in the polymers to exert tight control over mineralization and dissolution, but that the exact position of the charge in the polymer is of minor importance for both calcium phosphate precipitation and dissolution. London RSC Publishing 2015 12 RSC Advances : an international journal to further the chemical sciences 5 103494 103505 10.1039/c5ra20035k Institut für Chemie