TY  - GEN
A1  - Zehbe, Kerstin
A1  - Kollosche, Matthias
A1  - Lardong, Sebastian
A1  - Kelling, Alexandra
A1  - Schilde, Uwe
A1  - Taubert, Andreas
T1  - Ionogels based on poly(methyl methacrylate) and metal-containing ionic liquids
BT  - correlation between structure and mechanical and electrical properties
N2  - Ionogels (IGs) based on poly(methyl methacrylate) (PMMA) and the metal-containing ionic liquids (ILs) bis-1-butyl-3-methlimidazolium tetrachloridocuprate(II), tetrachloride cobaltate(II), and tetrachlorido manganate(II) have been synthesized and their mechanical and electrical properties have been correlated with their microstructure. Unlike many previous examples, the current IGs show a decreasing stability in stress-strain experiments on increasing IL fractions. The conductivities of the current IGs are lower than those observed in similar examples in the literature. Both effects are caused by a two-phase structure with micrometer-sized IL-rich domains homogeneously dispersed an IL-deficient continuous PMMA phase. This study demonstrates that the IL-polymer miscibility and the morphology of the IGs are key parameters to control the (macroscopic) properties of IGs.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 361 
KW  - microstructure
KW  - ionogels
KW  - ionic liquids
KW  - phase separation
KW  - mechanical properties
KW  - ionic conductivity
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-400607
ER  - 
TY  - JOUR
A1  - Zabel, André
A1  - Winter, Alette
A1  - Kelling, Alexandra
A1  - Schilde, Uwe
A1  - Strauch, Peter
T1  - Tetrabromidocuprates(II)-Synthesis, Structure and EPR
JF  - International journal of molecular sciences
N2  - Metal-containing ionic liquids (ILs) are of interest for a variety of technical applications, e.g., particle synthesis and materials with magnetic or thermochromic properties. In this paper we report the synthesis of, and two structures for, some new tetrabromidocuprates(II) with several “onium” cations in comparison to the results of electron paramagnetic resonance (EPR) spectroscopic analyses. The sterically demanding cations were used to separate the paramagnetic Cu(II) ions for EPR measurements. The EPR hyperfine structure in the spectra of these new compounds is not resolved, due to the line broadening resulting from magnetic exchange between the still-incomplete separated paramagnetic Cu(II) centres. For the majority of compounds, the principal g values (g|| and gK) of the tensors could be determined and information on the structural changes in the [CuBr4]2- anions can be obtained. The complexes have high potential, e.g., as ionic liquids, as precursors for the synthesis of copper bromide particles, as catalytically active or paramagnetic ionic liquids.
KW  - tetrabromidocuprate(II)
KW  - X-ray structure
KW  - electron paramagnetic resonance
KW  - copper(II)
Y1  - 2016
U6  - https://doi.org/10.3390/ijms17040596
VL  - 17
IS  - 4
PB  - MDPI
CY  - Basel
ER  - 
TY  - GEN
A1  - Zabel, André
A1  - Winter, Alette
A1  - Kelling, Alexandra
A1  - Schilde, Uwe
A1  - Strauch, Peter
T1  - Tetrabromidocuprates(II)-Synthesis, Structure and EPR
N2  - Metal-containing ionic liquids (ILs) are of interest for a variety of technical applications, e.g., particle synthesis and materials with magnetic or thermochromic properties. In this paper we report the synthesis of, and two structures for, some new tetrabromidocuprates(II) with several “onium” cations in comparison to the results of electron paramagnetic resonance (EPR) spectroscopic analyses. The sterically demanding cations were used to separate the paramagnetic Cu(II) ions for EPR measurements. The EPR hyperfine structure in the spectra of these new compounds is not resolved, due to the line broadening resulting from magnetic exchange between the still-incomplete separated paramagnetic Cu(II) centres. For the majority of compounds, the principal g values (g|| and gK) of the tensors could be determined and information on the structural changes in the [CuBr4]2- anions can be obtained. The complexes have high potential, e.g., as ionic liquids, as precursors for the synthesis of copper bromide particles, as catalytically active or paramagnetic ionic liquids.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 226 
KW  - tetrabromidocuprate(II)
KW  - X-ray structure
KW  - electron paramagnetic resonance
KW  - copper(II)
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-91470
ER  - 
TY  - JOUR
A1  - Wang, Xuepu
A1  - Sperling, Marcel
A1  - Reifarth, Martin
A1  - Böker, Alexander
T1  - Shaping metallic nanolattices
BT  - Design by microcontact printing from wrinkled stamps
JF  - Small
N2  - A method for the fabrication of well-defined metallic nanostructures is presented here in a simple and straightforward fashion. As an alternative to lithographic techniques, this routine employs microcontact printing utilizing wrinkled stamps, which are prepared from polydimethylsiloxane (PDMS), and includes the formation of hydrophobic stripe patterns on a substrate via the transfer of oligomeric PDMS. Subsequent backfilling of the interspaces between these stripes with a hydroxyl-functional poly(2-vinyl pyridine) then provides the basic pattern for the deposition of citrate-stabilized gold nanoparticles promoted by electrostatic interaction. The resulting metallic nanostripes can be further customized by peeling off particles in a second microcontact printing step, which employs poly(ethylene imine) surface-decorated wrinkled stamps, to form nanolattices. Due to the independent adjustability of the period dimensions of the wrinkled stamps and stamp orientation with respect to the substrate, particle arrays on the (sub)micro-scale with various kinds of geometries are accessible in a straightforward fashion. This work provides an alternative, cost-effective, and scalable surface-patterning technique to fabricate nanolattice structures applicable to multiple types of functional nanoparticles. Being a top-down method, this process could be readily implemented into, e.g., the fabrication of optical and sensing devices on a large scale.
KW  - gold nanoparticle assembly
KW  - hydroxyl-functional poly(2-vinyl pyridine)
KW  - metallic nanolattices
KW  - microcontact printing
KW  - oligomeric
KW  - polydimethylsiloxane
KW  - polydimethylsiloxane wrinkles
KW  - wrinkled stamps
Y1  - 2020
U6  - https://doi.org/10.1002/smll.201906721
SN  - 1613-6810
SN  - 1613-6829
VL  - 16
IS  - 11
SP  - 1
EP  - 8
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - GEN
A1  - Vioux, André
A1  - Taubert, Andreas
T1  - Ionic liquids 2014 and selected papers from ILMAT 2013
BT  - Highlighting the ever-growing potential of Ionic Liquids
T2  - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1055 
KW  - electrolytes
KW  - extraction
KW  - system
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-475062
SN  - 1866-8372
IS  - 1055
ER  - 
TY  - JOUR
A1  - Tung, Wing Tai
A1  - Sun, Xianlei
A1  - Wang, Weiwei
A1  - Xu, Xun
A1  - Ma, Nan
A1  - Lendlein, Andreas
T1  - Structure, mechanical properties and degradation behavior of electrospun PEEU fiber meshes and films
JF  - MRS advances : a journal of the Materials Research Society (MRS)
N2  - The capability of a degradable implant to provide mechanical support depends on its degradation behavior. Hydrolytic degradation was studied for a polyesteretherurethane (PEEU70), which consists of poly(p-dioxanone) (PPDO) and poly(epsilon-caprolactone) (PCL) segments with a weight ratio of 70:30 linked by diurethane junction units. PEEU70 samples prepared in the form of meshes with average fiber diameters of 1.5 mu m (mesh1.5) and 1.2 mu m (mesh1.2), and films were sterilized and incubated in PBS at 37 degrees C with 5 vol% CO2 supply for 1 to 6 weeks. Degradation features, such as cracks or wrinkles, became apparent from week 4 for all samples. Mass loss was found to be 11 wt%, 6 wt%, and 4 wt% for mesh1.2, mesh1.5, and films at week 6. The elongation at break decreased to under 20% in two weeks for mesh1.2. In case of the other two samples, this level of degradation was achieved after 4 weeks. The weight average molecular weight of both PEEU70 mesh and film samples decreased to below 30 kg/mol when elongation at break dropped below 20%. The time period of sustained mechanical stability of PEEU70-based meshes depends on the fiber diameter and molecular weight.
Y1  - 2021
U6  - https://doi.org/10.1557/s43580-020-00001-0
SN  - 2059-8521
VL  - 6
IS  - 10
SP  - 276
EP  - 282
PB  - Springer Nature Switzerland AG
CY  - Cham
ER  - 
TY  - JOUR
A1  - Tung, Wing Tai
A1  - Maring, Janita A.
A1  - Xu, Xun
A1  - Liu, Yue
A1  - Becker, Matthias
A1  - Somesh, Dipthi Bachamanda
A1  - Klose, Kristin
A1  - Wang, Weiwei
A1  - Sun, Xianlei
A1  - Ullah, Imran
A1  - Kratz, Karl
A1  - Neffe, Axel T.
A1  - Stamm, Christof
A1  - Ma, Nan
A1  - Lendlein, Andreas
T1  - In vivo performance of a cell and factor free multifunctional fiber mesh modulating postinfarct myocardial remodeling
JF  - Advanced Functional Materials
N2  - Guidance of postinfarct myocardial remodeling processes by an epicardial patch system may alleviate the consequences of ischemic heart disease. As macrophages are highly relevant in balancing immune response and regenerative processes their suitable instruction would ensure therapeutic success. A polymeric mesh capable of attracting and instructing monocytes by purely physical cues and accelerating implant degradation at the cell/implant interface is designed. In a murine model for myocardial infarction the meshes are compared to those either coated with extracellular matrix or loaded with induced cardiomyocyte progenitor cells. All implants promote macrophage infiltration and polarization in the epicardium, which is verified by in vitro experiments. 6 weeks post-MI, especially the implantation of the mesh attenuates left ventricular adverse remodeling processes as shown by reduced infarct size (14.7% vs 28-32%) and increased wall thickness (854 mu m vs 400-600 mu m), enhanced angiogenesis/arteriogenesis (more than 50% increase compared to controls and other groups), and improved heart function (ejection fraction = 36.8% compared to 12.7-31.3%). Upscaling as well as process controls is comprehensively considered in the presented mesh fabrication scheme to warrant further progression from bench to bedside.
KW  - bioinstructive materials
KW  - cardiac regeneration
KW  - function by structure;
KW  - modulation of in vivo regeneration
KW  - multifunctional biomaterials
Y1  - 2022
U6  - https://doi.org/10.1002/adfm.202110179
SN  - 1616-301X
SN  - 1616-3028
VL  - 32
IS  - 31
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Tao, Lumi
A1  - Liu, Yuchuan
A1  - Wu, Dan
A1  - Wei, Qiao-Hua
A1  - Taubert, Andreas
A1  - Xie, Zailai
T1  - Luminescent Ionogels with Excellent Transparency, High Mechanical Strength, and High Conductivity
JF  - Nanomaterials
N2  - The paper describes a new kind of ionogel with both good mechanical strength and high conductivity synthesized by confining the ionic liquid (IL) 1-butyl-3-methylimidazolium bis(trifluoromethane sulfonyl)imide ([Bmim][NTf₂]) within an organic–inorganic hybrid host. The organic–inorganic host network was synthesized by the reaction of methyltrimethoxysilane (MTMS), tetraethoxysilane (TEOS), and methyl methacrylate (MMA) in the presence of a coupling agent, offering the good mechanical strength and rapid shape recovery of the final products. The silane coupling agent 3-methacryloxypropyltrimethoxysilane (KH-570) plays an important role in improving the mechanical strength of the inorganic–organic hybrid, because it covalently connected the organic component MMA and the inorganic component SiO₂. Both the thermal stability and mechanical strength of the ionogel significantly increased by the addition of IL. The immobilization of [Bmim][NTf₂] within the ionogel provided the final ionogel with an ionic conductivity as high as ca. 0.04 S cm⁻¹ at 50 °C. Moreover, the hybrid ionogel can be modified with organosilica-modified carbon dots within the network to yield a transparent and flexible ionogel with strong excitation-dependent emission between 400 and 800 nm. The approach is, therefore, a blueprint for the construction of next-generation multifunctional ionogels.
KW  - ionic liquid
KW  - ionogel
KW  - carbon dots
KW  - organic–inorganic hybrid
KW  - luminescence
KW  - mechanical strength
Y1  - 2020
U6  - https://doi.org/10.3390/nano10122521
SN  - 2079-4991
VL  - 10
IS  - 12
PB  - MDPI
CY  - Basel
ER  - 
TY  - GEN
A1  - Tao, Lumi
A1  - Liu, Yuchuan
A1  - Wu, Dan
A1  - Wei, Qiao-Hua
A1  - Taubert, Andreas
A1  - Xie, Zailai
T1  - Luminescent Ionogels with Excellent Transparency, High Mechanical Strength, and High Conductivity
T2  - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - The paper describes a new kind of ionogel with both good mechanical strength and high conductivity synthesized by confining the ionic liquid (IL) 1-butyl-3-methylimidazolium bis(trifluoromethane sulfonyl)imide ([Bmim][NTf₂]) within an organic–inorganic hybrid host. The organic–inorganic host network was synthesized by the reaction of methyltrimethoxysilane (MTMS), tetraethoxysilane (TEOS), and methyl methacrylate (MMA) in the presence of a coupling agent, offering the good mechanical strength and rapid shape recovery of the final products. The silane coupling agent 3-methacryloxypropyltrimethoxysilane (KH-570) plays an important role in improving the mechanical strength of the inorganic–organic hybrid, because it covalently connected the organic component MMA and the inorganic component SiO₂. Both the thermal stability and mechanical strength of the ionogel significantly increased by the addition of IL. The immobilization of [Bmim][NTf₂] within the ionogel provided the final ionogel with an ionic conductivity as high as ca. 0.04 S cm⁻¹ at 50 °C. Moreover, the hybrid ionogel can be modified with organosilica-modified carbon dots within the network to yield a transparent and flexible ionogel with strong excitation-dependent emission between 400 and 800 nm. The approach is, therefore, a blueprint for the construction of next-generation multifunctional ionogels.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1058 
KW  - ionic liquid
KW  - ionogel
KW  - carbon dots
KW  - organic–inorganic hybrid
KW  - luminescence
KW  - mechanical strength
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-487334
SN  - 1866-8372
IS  - 1058
ER  - 
TY  - JOUR
A1  - Schönemann, Eric
A1  - Koc, Julian
A1  - Karthäuser, Jana
A1  - Özcan, Onur
A1  - Schanzenbach, Dirk
A1  - Schardt, Lisa
A1  - Rosenhahn, Axel
A1  - Laschewsky, André
T1  - Sulfobetaine methacrylate polymers of unconventional polyzwitterion architecture and their antifouling properties
JF  - Biomacromolecules : an interdisciplinary journal focused at the interface of polymer science and the biological sciences
N2  - Combining high hydrophilicity with charge neutrality, polyzwitterions are intensely explored for their high biocompatibility and low-fouling properties. Recent reports indicated that in addition to charge neutrality, the zwitterion's segmental dipole orientation is an important factor for interacting with the environment. Accordingly, a series of polysulfobetaines with a novel architecture was designed, in which the cationic and anionic groups of the zwitterionic moiety are placed at equal distances from the backbone. They were investigated by in vitro biofouling assays, covering proteins of different charges and model marine organisms. All polyzwitterion coatings reduced the fouling effectively compared to model polymer surfaces of poly(butyl methacrylate), with a nearly equally good performance as the reference polybetaine poly(3-(N-(2-(methacryloyloxy)ethyl)-N,N-dimethylammonio)propanesulfonate). The specific fouling resistance depended on the detailed chemical structure of the polyzwitterions. Still, while clearly affecting the performance, the precise dipole orientation of the sulfobetaine group in the polyzwitterions seems overall to be only of secondary importance for their antifouling behavior.
Y1  - 2021
U6  - https://doi.org/10.1021/acs.biomac.0c01705
SN  - 1525-7797
SN  - 1526-4602
VL  - 22
IS  - 4
SP  - 1494
EP  - 1508
PB  - American Chemical Society
CY  - Washington
ER  - 
TY  - JOUR
A1  - Schulze-Makuch, Dirk
A1  - Wagner, Dirk
A1  - Kounaves, Samuel P.
A1  - Mangelsdorf, Kai
A1  - Devine, Kevin G.
A1  - de Vera, Jean-Pierre
A1  - Schmitt-Kopplin, Philippe
A1  - Grossart, Hans-Peter
A1  - Parro, Victor
A1  - Kaupenjohann, Martin
A1  - Galy, Albert
A1  - Schneider, Beate
A1  - Airo, Alessandro
A1  - Froesler, Jan
A1  - Davila, Alfonso F.
A1  - Arens, Felix L.
A1  - Caceres, Luis
A1  - Cornejo, Francisco Solis
A1  - Carrizo, Daniel
A1  - Dartnell, Lewis
A1  - DiRuggiero, Jocelyne
A1  - Flury, Markus
A1  - Ganzert, Lars
A1  - Gessner, Mark O.
A1  - Grathwohl, Peter
A1  - Guan, Lisa
A1  - Heinz, Jacob
A1  - Hess, Matthias
A1  - Keppler, Frank
A1  - Maus, Deborah
A1  - McKay, Christopher P.
A1  - Meckenstock, Rainer U.
A1  - Montgomery, Wren
A1  - Oberlin, Elizabeth A.
A1  - Probst, Alexander J.
A1  - Saenz, Johan S.
A1  - Sattler, Tobias
A1  - Schirmack, Janosch
A1  - Sephton, Mark A.
A1  - Schloter, Michael
A1  - Uhl, Jenny
A1  - Valenzuela, Bernardita
A1  - Vestergaard, Gisle
A1  - Woermer, Lars
A1  - Zamorano, Pedro
T1  - Transitory microbial habitat in the hyperarid Atacama Desert
JF  - Proceedings of the National Academy of Sciences of the United States of America
KW  - habitat
KW  - aridity
KW  - microbial activity
KW  - biomarker
KW  - Mars
Y1  - 2018
U6  - https://doi.org/10.1073/pnas.1714341115
SN  - 0027-8424
VL  - 115
IS  - 11
SP  - 2670
EP  - 2675
PB  - National Acad. of Sciences
CY  - Washington
ER  - 
TY  - GEN
A1  - Sarauli, David
A1  - Xu, Chenggang
A1  - Dietzel, Birgit
A1  - Schulz, Burkhard
A1  - Lisdat, Fred
T1  - A multilayered sulfonated polyaniline network with entrapped pyrroloquinoline quinone-dependent glucose dehydrogenase
BT  - tunable direct bioelectrocatalysis
N2  - A feasible approach to construct multilayer films of sulfonated polyanilines – PMSA1 and PABMSA1 – containing different ratios of aniline, 2-methoxyaniline-5-sulfonic acid (MAS) and 3-aminobenzoic acid (AB), with the entrapped redox enzyme pyrroloquinoline quinone-dependent glucose dehydrogenase (PQQ-GDH) on Au and ITO electrode surfaces, is described. The formation of layers has been followed and confirmed by electrochemical impedance spectroscopy (EIS), which demonstrates that the multilayer assembly can be achieved in a progressive and uniform manner. The gold and ITO electrodes subsequently modified with PMSA1:PQQ-GDH and PABMSA1 films are studied by cyclic voltammetry (CV) and UV-Vis spectroscopy which show a significant direct bioelectrocatalytical response to the oxidation of the substrate glucose without any additional mediator. This response correlates linearly with the number of deposited layers. Furthermore, the constructed polymer/enzyme multilayer system exhibits a rather good long-term stability, since the catalytic current response is maintained for more than 60% of the initial value even after two weeks of storage. This verifies that a productive interaction of the enzyme embedded in the film of substituted polyaniline can be used as a basis for the construction of bioelectronic units, which are useful as indicators for processes liberating glucose and allowing optical and electrochemical transduction.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 275 
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-98744
ER  - 
TY  - JOUR
A1  - Sandmann, Michael
A1  - Münzberg, Marvin
A1  - Bressel, Lena
A1  - Reich, Oliver
A1  - Hass, Roland
T1  - Inline monitoring of high cell density cultivation of Scenedesmus rubescens in a mesh ultra-thin layer photobioreactor by photon density wave spectroscopy
JF  - BMC Research Notes / Biomed Central
N2  - Objective Due to multiple light scattering that occurs inside and between cells, quantitative optical spectroscopy in turbid biological suspensions is still a major challenge. This includes also optical inline determination of biomass in bioprocessing. Photon Density Wave (PDW) spectroscopy, a technique based on multiple light scattering, enables the independent and absolute determination of optical key parameters of concentrated cell suspensions, which allow to determine biomass during cultivation. Results A unique reactor type, called "mesh ultra-thin layer photobioreactor" was used to create a highly concentrated algal suspension. PDW spectroscopy measurements were carried out continuously in the reactor without any need of sampling or sample preparation, over 3 weeks, and with 10-min time resolution. Conventional dry matter content and coulter counter measurements have been employed as established offline reference analysis. The PBR allowed peak cell dry weight (CDW) of 33.4 g L-1. It is shown that the reduced scattering coefficient determined by PDW spectroscopy is strongly correlated with the biomass concentration in suspension and is thus suitable for process understanding. The reactor in combination with the fiber-optical measurement approach will lead to a better process management.
KW  - Photon density wave spectroscopy
KW  - Multiple light scattering
KW  - Process
KW  - analytical technology
KW  - Fiber-optical spectroscopy
KW  - Mesh ultra-thin layer
KW  - photobioreactor
Y1  - 2022
U6  - https://doi.org/10.1186/s13104-022-05943-2
SN  - 1756-0500
VL  - 15
IS  - 1
PB  - Biomed Central (London)
CY  - London
ER  - 
TY  - JOUR
A1  - Reschke, Stefan
A1  - Mebs, Stefan
A1  - Sigfridsson-Clauss, Kajsa G. V.
A1  - Kositzki, Ramona
A1  - Leimkühler, Silke
A1  - Haumann, Michael
T1  - Protonation and Sulfido versus Oxo Ligation Changes at the Molybdenum Cofactor in Xanthine Dehydrogenase (XDH) Variants Studied by X-ray Absorption Spectroscopy
JF  - Inorganic chemistry
N2  - Enzymes of the xanthine oxidase family are among the best characterized mononuclear molybdenum enzymes. Open questions about their mechanism of transfer of an oxygen atom to the substrate remain. The enzymes share a molybdenum cofactor (Moco) with the metal ion binding a molybdopterin (MPT) molecule via its dithiolene function and terminal sulfur and oxygen groups. For xanthine dehydrogenase (XDH) from the bacterium Rhodobacter capsulatus, we used X-ray absorption spectroscopy to determine the Mo site structure, its changes in a pH range of 5-10, and the influence of amino acids (Glu730 and Gln179) close to Moco in wild-type (WT), Q179A, and E730A variants, complemented by enzyme kinetics and quantum chemical studies. Oxidized WT and Q179A revealed a similar Mo (VI) ion with each one MPT, Mo=O, Mo-O-, and Mo=S ligand, and a weak Mo-O(E730) bond at alkaline pH. Protonation of an oxo to a hydroxo (OH) ligand (pK similar to 6.8) causes inhibition of XDH at acidic pH, whereas deprotonated xanthine (pK similar to 8.8) is an inhibitor at alkaline pH. A similar acidic pK for the WT and Q179A. variants, as well as the metrical parameters of the Mo site and density functional theory calculations, suggested protonation at the equatorial oxo group. The sulfido was replaced with an oxo ligand in the inactive E730A variant, further showing another oxo and one Mo OH ligand at Mo, which are independent of pH. Our findings suggest a reaction mechanism for XDH in which an initial oxo rather than a hydroxo group and the sulfido ligand are essential for xanthine oxidation.
Y1  - 2017
U6  - https://doi.org/10.1021/acs.inorgchem.6b02846
SN  - 0020-1669
SN  - 1520-510X
VL  - 56
IS  - 4
SP  - 2165
EP  - 2176
PB  - American Chemical Society
CY  - Washington
ER  - 
TY  - CHAP
A1  - Ramadan, Shahenda
A1  - Guerrero, Paula
A1  - Nedielkov, Ruslan
A1  - Klishin, Nikolai
A1  - Dimova, Rumiana
A1  - Silva, Daniel V.
A1  - Möller, Heiko
T1  - Building a mimetic system for unraveling protein-protein interactions on membranes
T2  - European biophysics journal : with biophysics letters ; an international journal of biophysics
Y1  - 2021
U6  - https://doi.org/10.1007/s00249-021-01558-w
SN  - 0175-7571
SN  - 1432-1017
VL  - 50
IS  - SUPPL 1
SP  - S153
EP  - S153
PB  - Springer
CY  - Berlin ; Heidelberg ; New York
ER  - 
TY  - JOUR
A1  - Raju, Rajarshi Roy
A1  - Koetz, Joachim
T1  - Inner rotation of Pickering Janus emulsions
JF  - Nanomaterials : open access journal
N2  - Janus droplets were prepared by vortex mixing of three non-mixable liquids, i.e., olive oil, silicone oil and water, in the presence of gold nanoparticles (AuNPs) in the aqueous phase and magnetite nanoparticles (MNPs) in the olive oil. The resulting Pickering emulsions were stabilized by a red-colored AuNP layer at the olive oil/water interface and MNPs at the oil/oil interface. The core–shell droplets can be stimulated by an external magnetic field. Surprisingly, an inner rotation of the silicon droplet is observed when MNPs are fixed at the inner silicon droplet interface. This is the first example of a controlled movement of the inner parts of complex double emulsions by magnetic manipulation via interfacially confined magnetic nanoparticles.
KW  - Janus droplets
KW  - Pickering emulsions
KW  - magnetic manipulation
KW  - gold nanoparticles
KW  - magnetite nanoparticles
Y1  - 2021
U6  - https://doi.org/10.3390/nano11123312
SN  - 2079-4991
VL  - 11
IS  - 12
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Piluso, Susanna
A1  - Vukicevie, Radovan
A1  - Nöchel, Ulrich
A1  - Braune, Steffen
A1  - Lendlein, Andreas
A1  - Neffe, Axel T.
T1  - Sequential alkyne-azide cycloadditions for functionalized gelatin hydrogel formation
JF  - European polymer journal
N2  - While click chemistry reactions for biopolymer network formation are attractive as the defined reactions may allow good control of the network formation and enable subsequent functionalization, tailoring of gelatin network properties over a wide range of mechanical properties has yet to be shown. Here, it is demonstrated that copper-catalyzed alkyne-azide cycloaddition of alkyne functionalized gelatin with diazides gave hydrogel networks with properties tailorable by the ratio of diazide to gelatin and diazide rigidity. 4,4′-diazido-2,2′-stilbenedisulfonic acid, which has been used as rigid crosslinker, yielded hydrogels with Young’s moduli E of 50–390 kPa and swelling degrees Q of 150–250 vol.%, while the more flexible 1,8-diazidooctane resulted in hydrogels with E = 125–280 kPa and Q = 225–470 vol.%. Storage moduli could be varied by two orders of magnitude (G′ = 100–20,000 Pa). An indirect cytotoxicity test did not show cytotoxic properties. Even when employing 1:1 ratios of alkyne and azide moieties, the hydrogels were shown to contain both, unreacted alkyne groups on the gelatin backbone as well as dangling chains carrying azide groups as shown by reaction with functionalized fluorescein. The free groups, which can be tailored by the employed ratio of the reactants, are accessible for covalent attachment of drugs, as was demonstrated by functionalization with dexamethasone. The sequential network formation and functionalization with click chemistry allows access to multifunctional materials relevant for medical applications.
KW  - Click chemistry
KW  - Hydrogel
KW  - Polymer functionalization
KW  - Biopolymer
KW  - Rheology
KW  - Multifunctionality
Y1  - 2018
U6  - https://doi.org/10.1016/j.eurpolymj.2018.01.017
SN  - 0014-3057
SN  - 1873-1945
VL  - 100
SP  - 77
EP  - 85
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Picconi, David
T1  - Nonadiabatic quantum dynamics of the coherent excited state intramolecular proton transfer of 10-hydroxybenzo[h]quinoline
JF  - Photochemical & photobiological sciences
N2  - The photoinduced nonadiabatic dynamics of the enol-keto isomerization of 10-hydroxybenzo[h]quinoline (HBQ) are studied computationally using high-dimensional quantum dynamics. The simulations are based on a diabatic vibronic coupling Hamiltonian, which includes the two lowest pi pi* excited states and a n pi* state, which has high energy in the Franck-Condon zone, but significantly stabilizes upon excited state intramolecular proton transfer. A procedure, applicable to large classes of excited state proton transfer reactions, is presented to parametrize this model using potential energies, forces and force constants, which, in this case, are obtained by time-dependent density functional theory. The wave packet calculations predict a time scale of 10-15 fs for the photoreaction, and reproduce the time constants and the coherent oscillations observed in time- resolved spectroscopic studies performed on HBQ. In contrast to the interpretation given to the most recent experiments, it is found that the reaction initiated by 1 pi pi* <- S-0 photoexcitation proceeds essentially on a single potential energy surface, and the observed coherences bear signatures of Duschinsky mode-mixing along the reaction path. The dynamics after the 2 pi pi* <- S-0 excitation are instead nonadiabatic, and the n pi* state plays a major role in the relaxation process. The simulations suggest a mainly active role of the proton in the isomerization, rather than a passive migration assisted by the vibrations of the benzoquinoline backbone. <br /> [GRAPHICS] <br /> .
KW  - Excited state proton transfer
KW  - Quantum dynamics
KW  - Nonadiabatic effects
KW  - Spectroscopy
KW  - Coherences
Y1  - 2021
U6  - https://doi.org/10.1007/s43630-021-00112-z
SN  - 1474-905X
SN  - 1474-9092
VL  - 20
IS  - 11
SP  - 1455
EP  - 1473
PB  - Springer
CY  - Heidelberg
ER  - 
TY  - GEN
A1  - Peter, Martin G.
T1  - Products of in vitro oxidation of N-acetyldopamine as possible components in the sclerotization of insect cuticle
N2  - [1-14C]-N-Acetyldopamine (NADA) was oxidized in the presence of methyl [3-3H]-β-alanate with mushroom tyrosinase. The complex mixture of reaction products was partly resolved by chromatographic procedures and analyzed by spectroscopic methods. Methyl-β-alanate is incorporated to only a small extent into oxidation products of NADA which inter alia are presumed to be oligomeric hydroxyquinones. After oxidation of [1-14C, 2-3H]-NADA with preparations from tanning Manduca sexta pupal cuticle, N-acetylnoradrenalin was identified as one of the products. Binding of radioactivity to melanin-like material was also observed. These results suggest that oxidation products different from those formulated usually for the crosslinkages between protein amino groups and N-acetyldopaquinone are deposited in darkly brown coloured insect cuticles during sclerotization.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 041 
KW  - N-acetyldopamine
KW  - sclerotization
KW  - tyrosinase; o-quinones
KW  - tanning agents
Y1  - 1980
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-16759
ER  - 
TY  - GEN
A1  - Niedl, Robert Raimund
A1  - Beta, Carsten
T1  - Hydrogel-driven paper-based microfluidics
N2  - Paper-based microfluidics provide an inexpensive, easy to use technology for point-of-care diagnostics in developing countries. Here, we combine paper-based microfluidic devices with responsive hydrogels to add an entire new class of functions to these versatile low-cost fluidic systems. The hydrogels serve as fluid reservoirs. In response to an external stimulus, e.g. an increase in temperature, the hydrogels collapse and release fluid into the structured paper substrate. In this way, chemicals that are either stored on the paper substrate or inside the hydrogel pads can be dissolved, premixed, and brought to reaction to fulfill specific analytic tasks. We demonstrate that multi-step sequences of chemical reactions can be implemented in a paper-based system and operated without the need for external precision pumps. We exemplify this technology by integrating an antibody-based E. coli test on a small and easy to use paper device.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 193 
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-81083
SP  - 2452
EP  - 2459
ER  -