@article{KammerKellingBaieretal.2009, author = {Kammer, Stefan and Kelling, Alexandra and Baier, Heiko and Mickler, Wulfhard and Dosche, Carsten and Rurack, Knut and Kapp, Andreas and Lisdat, Fred and Holdt, Hans-J{\"u}rgen}, title = {2,11-dialkylated 1,12-diazaperylene copper(I) complexes : first supramolecular column assemblies by pi-pi stacking between homoleptic tetrahedral metal complexes, exhibiting low-energy MLCT transitions}, issn = {1434-1948}, doi = {10.1002/ejic.200900695}, year = {2009}, abstract = {2,11-Dialkylated 1,12-diazaperylenes (alkyl = Me, Et, iPr) dmedap, detdap and dipdap have been synthesized by reductive cyclization of 3,3-dialkylated 1,1-biisoquinolines 3a-c, resulting in the first copper(I) complexes of a large- surface ligand. The new copper(I) complexes show low-energy MLCT absorptions unprecedented for bis(-diimin)copper(I) complexes. The solid structures of the complexes[Cu(dipdap)2]BF4·CH2Cl2·1.5H2O, [Cu(dipdap)2]OTf·CH2Cl2, [Cu(dipdap)2]I·C2H4Cl2·THF·2H2O, [Cu(dmedap)2]OTf and [Cu(dipdap)2]AQSO3·H2O (AQSO3 = sodium 9,10-dihydro-9,10-dioxo-2- anthracenesulfonate) are reported. In [Cu(dipdap)2]BF4·CH2Cl2·1.5H2O, each copper(I) complex cation interacts with two others by - stacking interactions forming a novel supramolecular column structural motif running along the crystallographic c axis. In the crystalline compound [Cu(dipdap)2]AQSO3·H2O, aggregation between two complex cations and two additional anions by - stacking interactions is observed, leading to a tetrameric assembly. Furthermore, the three complex compounds [Cu(L)2]BF4 (L = dmedap, detdap, dipdap) were tested for sensory applications in aqueous buffer solutions in electrochemical studies of the complex immobilized on glassy carbon electrodes.}, language = {en} } @article{SarauliPetersXuetal.2014, author = {Sarauli, David and Peters, Kristina and Xu, Chenggang and Schulz, Burkhard and Fattakhova-Rohlfing, Dina and Lisdat, Fred}, title = {3D-Electrode architectures for enhanced direct bioelectrocatalysis of pyrroloquinoline quinone-dependent glucose dehydrogenase}, series = {ACS applied materials \& interfaces}, volume = {6}, journal = {ACS applied materials \& interfaces}, number = {20}, publisher = {American Chemical Society}, address = {Washington}, issn = {1944-8244}, doi = {10.1021/am5046026}, pages = {17887 -- 17893}, year = {2014}, abstract = {We report on the fabrication of a complex electrode architecture for efficient direct bioelectrocatalysis. In the developed procedure, the redox enzyme pyrroloquinoline quinone-dependent glucose dehydrogenase entrapped in a sulfonated polyaniline [poly(2-methoxyaniline-5-sulfonic acid)-co-aniline] was immobilized on macroporous indium tin oxide (macroITO) electrodes. The use of the 3D-conducting scaffold with a large surface area in combination with the conductive polymer enables immobilization of large amounts of enzyme and its efficient communication with the electrode, leading to enhanced direct bioelectrocatalysis. In the presence of glucose, the fabricated bioelectrodes show an exceptionally high direct bioelectrocatalytical response without any additional mediator. The catalytic current is increased more than 200-fold compared to planar ITO electrodes. Together with a high long-term stability (the current response is maintained for >90\% of the initial value even after 2 weeks of storage), the transparent 3D macroITO structure with a conductive polymer represents a valuable basis for the construction of highly efficient bioelectronic units, which are useful as indicators for processes liberating glucose and allowing optical and electrochemical transduction.}, language = {en} } @misc{SarauliXuDietzeletal.2014, author = {Sarauli, David and Xu, Chenggang and Dietzel, Birgit and Schulz, Burkhard and Lisdat, Fred}, title = {A multilayered sulfonated polyaniline network with entrapped pyrroloquinoline quinone-dependent glucose dehydrogenase}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-98744}, year = {2014}, abstract = {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.}, language = {en} } @article{SarauliXuDietzeletal.2014, author = {Sarauli, David and Xu, Chenggang and Dietzel, Birgit and Schulz, Burkhard and Lisdat, Fred}, title = {A multilayered sulfonated polyaniline network with entrapped pyrroloquinoline quinone-dependent glucose dehydrogenase: tunable direct bioelectrocatalysis}, series = {Journal of materials chemistry : B, Materials for biology and medicine}, volume = {2}, journal = {Journal of materials chemistry : B, Materials for biology and medicine}, number = {21}, publisher = {Royal Society of Chemistry}, address = {Cambridge}, issn = {2050-750X}, doi = {10.1039/c4tb00336e}, pages = {3196 -- 3203}, year = {2014}, abstract = {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.}, language = {en} } @article{BeissenhirtzSchellerLisdat2004, author = {Beissenhirtz, Moritz Karl and Scheller, Frieder W. and Lisdat, Fred}, title = {A superoxide sensor based on a multilayer cytochrome c electrode}, issn = {0003-2700}, year = {2004}, abstract = {A novel multilayer cytochrome c electrode for the quantification of superoxide radical concentrations is introduced. The electrode consists of alternating layers of cytochrome c and poly(aniline(sulfonic acid)) on a gold wire electrode. The formation of multilayer structures was proven by SPR experiments. Assemblies with 2-15 protein layers showed electrochemical communication with the gold electrode. For every additional layer, a substantial increase in electrochemically active cytochrome c (cyt. c) was found. For electrodes of more than 10 layers, the increase was more than 1 order of magnitude as compared to monolayer electrode systems. Thermodynamic and kinetic parameters of the electrodes were characterized. The mechanism of electron transfer within the multilayer assembly was studied, with results suggesting a protein-protein electron-transfer model. Electrodes of 2-15 layers were applied to the in vitro quantification of enzymatically generated superoxide, showing superior sensitivity as compared to a monolayer-based sensor. An electrode with 6 cyt. c/PASA layers showed the highest sensitivity of the systems studied, giving an increase in sensitivity of half an order of magnitude versus the that of the monolayer electrode. The stability of the system was optimized using thermal treatment, resulting in no loss in sensor signal or protein loading after 10 successive measurements or 2 days of storage}, language = {en} } @article{IgnatovShishniashviliGeetal.2002, author = {Ignatov, S. and Shishniashvili, D. and Ge, Bixia and Scheller, Frieder W. and Lisdat, Fred}, title = {Amperometric biosensor based on a functionalized gold electrode for the detection of antioxidants}, year = {2002}, language = {en} } @article{LisdatGeReszkaetal.1999, author = {Lisdat, Fred and Ge, Bixia and Reszka, R. and Kozniewska, E.}, title = {An electrochemical method for quantification of the radical scavening activity of SOD}, year = {1999}, language = {en} } @article{LisdatUtepbergenovHaseloffetal.2001, author = {Lisdat, Fred and Utepbergenov, D. and Haseloff, R. F. and Blasig, Ingolf E. and St{\"o}cklein, Walter F. M. and Scheller, Frieder W. and Brigelius-Floh{\´e}, Regina}, title = {An optical method for the detection of oxidative stress using protein-RNA interaction}, year = {2001}, language = {en} } @article{SchellerLisdatWollenberger2005, author = {Scheller, Frieder W. and Lisdat, Fred and Wollenberger, Ursula}, title = {Application of electrically contacted enzymes for biosensors}, isbn = {3-527- 30690-0}, year = {2005}, language = {en} } @article{SchellerWollenbergerLeietal.2002, author = {Scheller, Frieder W. and Wollenberger, Ursula and Lei, Chenghong and Jin, Wen and Ge, Bixia and Lehmann, Claudia and Lisdat, Fred and Fridman, Vadim}, title = {Bioelectrocatalysis by redox enzymes at modified electrodes}, year = {2002}, language = {en} }