TY  - JOUR
A1  - Jetzschmann, Katharina J.
A1  - Jagerszki, Gyula
A1  - Dechtrirat, Decha
A1  - Yarman, Aysu
A1  - Gajovic-Eichelmann, Nenad
A1  - Gilsing, Hans-Detlev
A1  - Schulz, Burkhard
A1  - Gyurcsanyi, Robert E.
A1  - Scheller, Frieder W.
T1  - Vectorially Imprinted Hybrid Nanofilm for Acetylcholinesterase Recognition
JF  - Advanced functional materials
N2  - Effective recognition of enzymatically active tetrameric acetylcholinesterase (AChE) is accomplished by a hybrid nanofilm composed of a propidium-terminated self-assembled monolayer (Prop-SAM) which binds AChE via its peripheral anionic site (PAS) and an ultrathin electrosynthesized molecularly imprinted polymer (MIP) cover layer of a novel carboxylate-modified derivative of 3,4-propylenedioxythiophene. The rebinding of the AChE to the MIP/Prop-SAM nanofilm covered electrode is detected by measuring in situ the enzymatic activity. The oxidative current of the released thiocholine is dependent on the AChE concentration from approximate to 0.04 x 10(-6) to 0.4 x 10(-6)m. An imprinting factor of 9.9 is obtained for the hybrid MIP, which is among the best values reported for protein imprinting. The dissociation constant characterizing the strength of the MIP-AChE binding is 4.2 x 10(-7)m indicating the dominant role of the PAS-Prop-SAM interaction, while the benefit of the MIP nanofilm covering the Prop-SAM layer is the effective suppression of the cross-reactivity toward competing proteins as compared with the Prop-SAM. The threefold selectivity gain provided by i) the shape-specific MIP filter, ii) the propidium-SAM, iii) signal generation only by the AChE bound to the nanofilm shows promise for assessing AChE activity levels in cerebrospinal fluid.
KW  - acetylcholinesterase
KW  - biomimetic sensors
KW  - molecularly imprinted electropolymers
KW  - peripheral anionic site
KW  - propidium
Y1  - 2015
U6  - https://doi.org/10.1002/adfm.201501900
SN  - 1616-301X
SN  - 1616-3028
VL  - 25
IS  - 32
SP  - 5178
EP  - 5183
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Reiche, Jürgen
A1  - Freydank, Anke-Christine
A1  - Helms, Andreas
A1  - Geue, Thomas
A1  - Schulz, Burkhard
A1  - Brehmer, Ludwig
A1  - Stiller, Burkhard
A1  - Knochenhauer, Gerald
T1  - Vacuum deposition films of oxadiazole compounds : formation and structure investigation
N2  - The search for alternative routes of organic thin film formation is stimulated by the outstanding properties of these films in such fields as nonlinear optics, photonic data processing and molecular electronics. The formation of highly ordered multilayer structures by thermal vacuum deposition (VD) of organic compounds is an essential step toward the application of supramolecular organic architectures in technical systems. The VD of an amphiphilic substituted 2,5- diphenylene-1,3,4-oxadiazole 1 onto silicon substrates at defined temperature was used for the formation of ultrathin films. The structural data obtained for the VD-films of oxadiazole 1 by means of X-ray reflectivity, X-ray grazing incidence diffraction and atomic force microscopy (AFM) investigations indicate the formation of well ordered oxadiazole multilayers. The structure of the VD-multilayers is compared with that of Langmuir-Blodgett (LB) films and thermally treated LB-multilayers prepared from the same compound.
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Diez, Isabel
A1  - Tauer, Klaus
A1  - Schulz, Burkhard
T1  - Unusual polymer dispersions-polypyrrole suspensions made of rings, frames, and platelets
JF  - Colloid and polymer science : official journal of the Kolloid-Gesellschaft
N2  - Experimental results show that the polymerization of pyrrole in the presence of beta-naphthalenesulfonic acid and different fluorosurfactants like perfluorooctanesulfonic acid, perfluorooctyldiethanolamide, and ammonium perfluorooctanoate leads to polypyrrole with special morphologies, such as rings or disks and rectangular frames or plates. The formation of these unusually shaped particles of polymer dispersions is explained by the chemical and colloidal peculiarities of the oxidative pyrrole polymerization with ammonium peroxodisulfate in aqueous medium.
KW  - polypyrrole
KW  - chemical oxidative polymerization
KW  - particle morphology
Y1  - 2006
U6  - https://doi.org/10.1007/s00396-006-1521-8
SN  - 0303-402X
VL  - 284
SP  - 1431
EP  - 1442
PB  - Springer
CY  - New York
ER  - 
TY  - JOUR
A1  - Schürmann, H.
A1  - Koch, Norbert
A1  - Imperia, Paolo
A1  - Schrader, Sigurd
A1  - Jandke, M.
A1  - Strohriegl, P.
A1  - Schulz, Burkhard
A1  - Leising, G.
A1  - Brehmer, Ludwig
T1  - Ultraviolet photoelectron spectroscopic study of heterocyclic model compounds for electroluminescent devices
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Sarauli, David
A1  - Xu, Chenggang
A1  - Dietzel, Birgit
A1  - Stiba, Konstanze
A1  - Leimkühler, Silke
A1  - Schulz, Burkhard
A1  - Lisdat, Fred
T1  - Thin films of substituted polyanilines interactions with biomolecular systems
JF  - Soft matter
N2  - We use substituted polyanilines for the construction of new polymer electrodes for interaction studies with the redox protein cytochrome c (cyt c) and the enzyme sulfite oxidase (SO). For these purposes four different polyaniline copolymers are chemically synthesized. Three of them are copolymers, containing 2-methoxyaniline-5-sulfonic acid with variable ratios of aniline; the fourth copolymer consists of 3-amino-benzoic acid and aniline. The results show that all polymers are suitable for being immobilized as thin stable films on gold wire and indium tin oxide (ITO) electrode surfaces from DMSO solution. This can be demonstrated by cyclic voltammetry and UV-Vis spectroscopy measurements. Moreover, cyt c can be electrochemically detected not only in solution, but also immobilized on top of the polymer films. Furthermore, the appearance of a significant catalytic current has been demonstrated for the sulfonated polyanilines, when the polymer-coated protein electrode is being measured upon addition of sulfite oxidase, confirming the establishment of a bioanalytical signal chain. Best results have been obtained for the polymer with highest sulfonation grade. The redox switching of the polymer by the enzymatic reaction can also be analyzed by following the spectral properties of the polymer electrode.
Y1  - 2012
U6  - https://doi.org/10.1039/c2sm07261k
SN  - 1744-683X
VL  - 8
IS  - 14
SP  - 3848
EP  - 3855
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  - 
TY  - JOUR
A1  - Okatova, Olga V.
A1  - Andreeva, Katharina A.
A1  - Schulz, Burkhard
T1  - Thermal hydrolytic degradation of polyoxadiazole derivatives
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Banks, Jo Ann
A1  - Nishiyama, Tomoaki
A1  - Hasebe, Mitsuyasu
A1  - Bowman, John L.
A1  - Gribskov, Michael
A1  - dePamphilis, Claude
A1  - Albert, Victor A.
A1  - Aono, Naoki
A1  - Aoyama, Tsuyoshi
A1  - Ambrose, Barbara A.
A1  - Ashton, Neil W.
A1  - Axtell, Michael J.
A1  - Barker, Elizabeth
A1  - Barker, Michael S.
A1  - Bennetzen, Jeffrey L.
A1  - Bonawitz, Nicholas D.
A1  - Chapple, Clint
A1  - Cheng, Chaoyang
A1  - Correa, Luiz Gustavo Guedes
A1  - Dacre, Michael
A1  - DeBarry, Jeremy
A1  - Dreyer, Ingo
A1  - Elias, Marek
A1  - Engstrom, Eric M.
A1  - Estelle, Mark
A1  - Feng, Liang
A1  - Finet, Cedric
A1  - Floyd, Sandra K.
A1  - Frommer, Wolf B.
A1  - Fujita, Tomomichi
A1  - Gramzow, Lydia
A1  - Gutensohn, Michael
A1  - Harholt, Jesper
A1  - Hattori, Mitsuru
A1  - Heyl, Alexander
A1  - Hirai, Tadayoshi
A1  - Hiwatashi, Yuji
A1  - Ishikawa, Masaki
A1  - Iwata, Mineko
A1  - Karol, Kenneth G.
A1  - Koehler, Barbara
A1  - Kolukisaoglu, Uener
A1  - Kubo, Minoru
A1  - Kurata, Tetsuya
A1  - Lalonde, Sylvie
A1  - Li, Kejie
A1  - Li, Ying
A1  - Litt, Amy
A1  - Lyons, Eric
A1  - Manning, Gerard
A1  - Maruyama, Takeshi
A1  - Michael, Todd P.
A1  - Mikami, Koji
A1  - Miyazaki, Saori
A1  - Morinaga, Shin-ichi
A1  - Murata, Takashi
A1  - Müller-Röber, Bernd
A1  - Nelson, David R.
A1  - Obara, Mari
A1  - Oguri, Yasuko
A1  - Olmstead, Richard G.
A1  - Onodera, Naoko
A1  - Petersen, Bent Larsen
A1  - Pils, Birgit
A1  - Prigge, Michael
A1  - Rensing, Stefan A.
A1  - Mauricio Riano-Pachon, Diego
A1  - Roberts, Alison W.
A1  - Sato, Yoshikatsu
A1  - Scheller, Henrik Vibe
A1  - Schulz, Burkhard
A1  - Schulz, Christian
A1  - Shakirov, Eugene V.
A1  - Shibagaki, Nakako
A1  - Shinohara, Naoki
A1  - Shippen, Dorothy E.
A1  - Sorensen, Iben
A1  - Sotooka, Ryo
A1  - Sugimoto, Nagisa
A1  - Sugita, Mamoru
A1  - Sumikawa, Naomi
A1  - Tanurdzic, Milos
A1  - Theissen, Guenter
A1  - Ulvskov, Peter
A1  - Wakazuki, Sachiko
A1  - Weng, Jing-Ke
A1  - Willats, William W. G. T.
A1  - Wipf, Daniel
A1  - Wolf, Paul G.
A1  - Yang, Lixing
A1  - Zimmer, Andreas D.
A1  - Zhu, Qihui
A1  - Mitros, Therese
A1  - Hellsten, Uffe
A1  - Loque, Dominique
A1  - Otillar, Robert
A1  - Salamov, Asaf
A1  - Schmutz, Jeremy
A1  - Shapiro, Harris
A1  - Lindquist, Erika
A1  - Lucas, Susan
A1  - Rokhsar, Daniel
A1  - Grigoriev, Igor V.
T1  - The selaginella genome identifies genetic changes associated with the evolution of vascular plants
JF  - Science
N2  - Vascular plants appeared similar to 410 million years ago, then diverged into several lineages of which only two survive: the euphyllophytes (ferns and seed plants) and the lycophytes. We report here the genome sequence of the lycophyte Selaginella moellendorffii (Selaginella), the first nonseed vascular plant genome reported. By comparing gene content in evolutionarily diverse taxa, we found that the transition from a gametophyte- to a sporophyte-dominated life cycle required far fewer new genes than the transition from a nonseed vascular to a flowering plant, whereas secondary metabolic genes expanded extensively and in parallel in the lycophyte and angiosperm lineages. Selaginella differs in posttranscriptional gene regulation, including small RNA regulation of repetitive elements, an absence of the trans-acting small interfering RNA pathway, and extensive RNA editing of organellar genes.
Y1  - 2011
U6  - https://doi.org/10.1126/science.1203810
SN  - 0036-8075
VL  - 332
IS  - 6032
SP  - 960
EP  - 963
PB  - American Assoc. for the Advancement of Science
CY  - Washington
ER  - 
TY  - JOUR
A1  - Schöne, Anne-Christin
A1  - Kratz, Karl
A1  - Schulz, Burkhard
A1  - Lendlein, Andreas
T1  - The relevance of hydrophobic segments in multiblock copolyesterurethanes for their enzymatic degradation at the air-water interface
JF  - Polymer : the international journal for the science and technology of polymers
N2  - The interplay of an enzyme with a multiblock copolymer PDLCL containing two segments of different hydrophilicity and degradability is explored in thin films at the air-water interface. The enzymatic degradation was studied in homogenous Langmuir monolayers, which are formed when containing more than 40 wt% oligo(epsilon-caprolactone) (OCL). Enzymatic degradation rates were significantly reduced with increasing content of hydrophobic oligo(omega-pentadecalactone) (OPDL). The apparent deceleration of the enzymatic process is caused by smaller portion of water-soluble degradation fragments formed from degradable OCL fragments. Beside the film degradation, a second competing process occurs after adding lipase from Pseudomonas cepacia into the subphase, namely the enrichment of the lipase molecules in the polymeric monolayer. The incorporation of the lipase into the Langmuir film is experimentally revealed by concurrent surface area enlargement and by Brewster angle microscopy (BAM). Aside from the ability to provide information about the degradation behavior of polymers, the Langmuir monolayer degradation (LMD) approach enables to investigate polymer-enzyme interactions for non-degradable polymers. (C) 2016 Elsevier Ltd. All rights reserved.
KW  - Multiblock copolymer
KW  - Enzymatic polymer degradation
KW  - Oligo(omega-pentadecalactone)
KW  - Oligo(epsilon-caprolactone)
KW  - Langmuir monolayer degradation technique
Y1  - 2016
U6  - https://doi.org/10.1016/j.polymer.2016.09.001
SN  - 0032-3861
SN  - 1873-2291
VL  - 102
SP  - 92
EP  - 98
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Machatschek, Rainhard Gabriel
A1  - Schulz, Burkhard
A1  - Lendlein, Andreas
T1  - The influence of pH on the molecular degradation mechanism of PLGA
JF  - MRS Advances
N2  - Poly[(rac-lactide)-co-glycolide] (PLGA) is used in medicine to provide mechanical support for healing tissue or as matrix for controlled drug release. The properties of this copolymer depend on the evolution of the molecular weight of the material during degradation. which is determined by the kinetics of the cleavage of hydrolysable bonds. The generally accepted description of the degradation of PLGA is a random fragmentation that is autocatalyzed by the accumulation of acidic fragments inside the bulk material. Since mechanistic studies with lactide oligomers have concluded a chain-end scission mechanism and monolayer degradation experiments with polylactide found no accelerated degradation at lower pH, we hypothesize that the impact of acidic fragments on the molecular degradation kinetics of PLGA is overestimated By means of the Langmuir monolayer degradation technique. the molecular degradation kinetics of PLGA at different pH could be determined. Protons did not catalyze the degradation of PLGA. The molecular mechanism at neutral pH and low pH is a combination of random and chainend-cut events, while the degradation under strongly alkaline conditions is determined by rapid chainend cuts. We suggest that the degradation of bulk PLGA is not catalyzed by the acidic degradation products. Instead. increased concentration of small fragments leads to accelerated mass loss via fast chain-end cut events. In the future, we aim to substantiate the proposed molecular degradation mechanism of PLGA with interfacial rheology.
Y1  - 2018
U6  - https://doi.org/10.1557/adv.2018.602
SN  - 2059-8521
VL  - 3
IS  - 63
SP  - 3883
EP  - 3889
PB  - Cambridge Univ. Press
CY  - New York
ER  - 
TY  - JOUR
A1  - Schulz, Burkhard
A1  - Orgzall, Ingo
A1  - Diez, Isabel
A1  - Dietzel, Birgit
A1  - Tauer, Klaus
T1  - Template mediated formation of shaped polypyrrole particles
N2  - The formation of different micro- and nanostructures during the chemical synthesis of polypyrrole is reviewed shortly based on the conceptions of hard- and soft-templating models. Contrary to other models that emphasize the role of micelles it is found here that during the oxidative polymerization of pyrole using sulfonic acid dopants a crystalline hard template is found in the first steps of the reaction before the addition of the oxidant. This template is formed by a complex consisting of 2,5-bis(pyrrole-2-yl)pyrrolidine and the sulfonic acid anion. The acid catalyzed formation of this specific tripyrrole is discussed. (C) 2009 Elsevier B.V. All rights reserved.
Y1  - 2010
U6  - https://doi.org/10.1016/j.colsurfa.2009.11.034
SN  - 0927-7757
ER  - 
TY  - JOUR
A1  - Bruma, Maria
A1  - Hamciuc, Elena
A1  - Schulz, Burkhard
A1  - Köpnick, Thomas
A1  - Stiller, Burkhard
A1  - Mercer, Frank W.
T1  - Synthesis of fluorinated poly(phenylquinoxaline-amide)s and study of thin films made therefrom
N2  - A series of five fluorinated poly(phenylquinoxaline-amide)s were synthesized by a polycondensation reaction of a diacid chloride containing the hexafluoroisopropylidene (6F) group, namely 2,2-bis(p-chlorocarbonylphenyl)- hexafluoropropane, with various aromatic diamines incorporating two phenyl-substituted quinoxaline rings. These polymers were easily soluble in polar aprotic solvents such as N-methylpyrrolione (NMP), dimethylformamide (DMF), and tetrahydrofurane (THF), and showed a high thermal stability with decomposition temperatures above 400 °C and glass transition temperatures in the range of 260-290 Tg. Polymer solutions in NMP were processed into free-standing films that showed low dielectric constant values, in the range of 3.4-3.9, and good mechanical properties, with tensile strength in the range of 40-80 MPa and elongation to break in the range of 22-55%. Very thin films, in the range of tens of nanometer, which were deposited onto silicon wafers exhibited very smooth surfaces, free of pinholes when studied by atomic force microscopy (AFM).
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Hamaciuc, E.
A1  - Bruma, Maria
A1  - Köpnick, Thomas
A1  - Kaminorz, Yvette
A1  - Schulz, Burkhard
T1  - Synthesis and Study of New Silicon-containing Polyoxadiazoles
N2  - A series of new poly-1,3,4-oxadiazoles has been synthesized by polycondensation reaction of hydrazine sulfate with a mixture of a dicarboxylic acid containing unsaturated bonds and a dicarboxylic acid containing silicon, by using methanesulfonic acid/phosphorus pentoxide as a reaction medium. These polymers were highly thermostable but they were only soluble in strong inorganic acids such as sulfuric or methanesulfonic ones. An alternative way was followed by using the corresponding dihydrazides containing unsaturated bonds and the corresponding diacid chloride containing silicon that reacted in N-methylpyrrolidinone (NMP) to give soluble silicon-containing unsaturated polyhydrazides, which were cyclodehydrated either by thermal or chemical treatment to give the corresponding polyoxadiazoles. Very thin coatings of polyhydrazides and polyoxadiazoles were deposited onto silicon wafers and they showed a very smooth surface, free of pinholes, when studied by atomic force microscopy (AFM). Some polyoxadiazole films showed strong blue photoluminescence.
Y1  - 2001
ER  - 
TY  - JOUR
A1  - Bruma, Maria
A1  - Schulz, Burkhard
A1  - Köpnick, Thomas
A1  - Stiller, Burkhard
A1  - Belomoina, Nataliya
A1  - Mercer, Frank W.
T1  - Synthesis and study of aromatic polyamides containing silicon and phenylquinoxaline rings in the main chain
N2  - New poly(phenylquinoxaline-amide)s with silicon in the main chain have been prepared by polycondensation reaction of a diacid chloride, namely bis(p-chlorocarbonyl-phenyl)-diphenylsilane, with aromatic diamines containing one or two phenylquinoxaline rings separated by a flexible bridge such as ether or methylene. These polymers were easily soluble in polar aprotic solvents such as N-methylpyrrolidinone (NMP) and dimethylformamide (DMF) and showed high thermal stability with decomposition temperature being above 450°C and glass transition temperature in the range of 260- 304°C. Polymer solutions in NMP were processed into thin flexible films which exhibited very smooth surfaces, free of pinholes when studied by atomic force microscopy. The free-standing films showed a dielectric constant in the range of 3.6-3.7.
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Sava, Ion
A1  - Bruma, Maria
A1  - Schulz, Burkhard
A1  - Mercer, Frank W.
A1  - Belomoina, Nataliya
T1  - Synthesis and Properties of Silicon-containing Polyamides
N2  - A series of aromatic polyamides incorporating silicon together with phenylquinoxaline or with hexafluoroisopropylidene groups has been synthesized by solution polycondensation of a silicon-containing diacid chloride with aromatic diamines having phenylquinoxaline rings or hexafluoroisopropylidene groups. These polymers are easily soluble in polar aprotic solvents, such as N-methylpyrrolidinone and dimethylformamide, and in tetrahydrofurane, and can be solution-cast into thin, transparent films having low dielectric constant, in the range of 3.26 to 3.68. These polymers show high thermal stability with decomposition temperature being above 400 °C and glass transition temperature in the range of 236 °C to 275 °C.
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Mercer, Frank W.
A1  - McKenzie, M.
A1  - Bruma, Maria
A1  - Schulz, Burkhard
T1  - Synthesis and properties of fluorinated polyimides and fluorinated poly(imide-amide)s containing pendent cyano groups
Y1  - 1994
ER  - 
TY  - JOUR
A1  - Lavrenko, Peter N.
A1  - Schulz, Burkhard
A1  - Strelina, Irina A.
A1  - Okatova, Olga V.
T1  - Synthesis and molecular properties of new poly(naphthalene-1,3,4-oxadiazole)s
N2  - Poly[(1,4-naphthalene)-2,5-diyl-1,3,4-oxadiazole] and poly[(2,6-naphthalene)-2,5-diyl-1,3,4-oxadiazole] have been synthesized and investigated in conc. H2S04, by the flow birefringence method in comparison with poly(1,4- phenylene)-2,5-diyl-1,3,4-oxadiazole]. Changes in conformation parameters and optical anisotropy of a chain unit induced by incorporation of the naphthalene groups into the macromolecule backbone have been evaluated.
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Freydank, Anke-Christine
A1  - Janietz, Silvia
A1  - Schulz, Burkhard
T1  - Synthesis and electrochemical characterization of new amphiphilic 1,3,4-oxadiazoles
N2  - The electrochemical behaviour of new amphiphilic 1,3,4-oxadiazoles were studied by cyclic voltammetry. The influence of the supra- molecular structure on the redox behaviour in liquid or solid solutions, in Langmuir-Blodgett multilayers, and in amorphous films is investigated in detail. The reversible reduction of amphiphilic 2,5-diarylene- 1,3,4-oxadiazoles is significantly influenced by substituents in the para position of the phenylene ring. In the solid states the reduction peak potentials are shifted to more negative values compared to data measured in solution. This shift increases as the film thickness is increased. An influence of the supramolecular order in the solid films was not found. In-situ UV-vis spectroelectrochemistry of LB-multilayers deposited onto indium tin oxide (ITO) glass give evidence for the formation of radical anions in the highly ordered layer.
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Freydank, Anke-Christine
A1  - Janietz, Silvia
A1  - Schulz, Burkhard
T1  - Synthesis and electrochemical behaviour of Amphiphilic 1,3,4-Oxadiazole derivatives
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Sava, Ion
A1  - Schulz, Burkhard
A1  - Zhu, Shigen
A1  - Bruma, Maria
T1  - Synthesis and characterization of new silicon-containing poly(arylene-1,3,4-oxadiazole)s
Y1  - 1995
UR  - http://hip.sagepub.com/
U6  - https://doi.org/10.1088/0954-0083/7/4/011
SN  - 0954-0083
ER  - 
TY  - JOUR
A1  - Bruma, Maria
A1  - Schulz, Burkhard
A1  - Mercer, Frank W.
T1  - Synthesis and characterization of fluorinated poly(imide-pyridazine- amide)s
Y1  - 1994
ER  -