@article{AltintasTakidenUteschetal.2019, author = {Altintas, Zeynep and Takiden, Aref and Utesch, Tillmann and Mroginski, Maria A. and Schmid, Bianca and Scheller, Frieder W. and S{\"u}ssmuth, Roderich D.}, title = {Integrated approaches toward high-affinity artificial protein binders obtained via computationally simulated epitopes for protein recognition}, series = {Advanced functional materials}, volume = {29}, journal = {Advanced functional materials}, number = {15}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1616-301X}, doi = {10.1002/adfm.201807332}, pages = {11}, year = {2019}, abstract = {Widely used diagnostic tools make use of antibodies recognizing targeted molecules, but additional techniques are required in order to alleviate the disadvantages of antibodies. Herein, molecular dynamic calculations are performed for the design of high affinity artificial protein binding surfaces for the recognition of neuron specific enolase (NSE), a known cancer biomarker. Computational simulations are employed to identify particularly stabile secondary structure elements. These epitopes are used for the subsequent molecular imprinting, where surface imprinting approach is applied. The molecular imprints generated with the calculated epitopes of greater stability (Cys-Ep1) show better binding properties than those of lower stability (Cys-Ep5). The average binding strength of imprints created with stabile epitopes is found to be around twofold and fourfold higher for the NSE derived peptide and NSE protein, respectively. The recognition of NSE is investigated in a wide concentration range, where high sensitivity (limit of detection (LOD) = 0.5 ng mL(-1)) and affinity (dissociation constant (K-d) = 5.3 x 10(-11)m) are achieved using Cys-Ep1 imprints reflecting the stable structure of the template molecules. This integrated approach employing stability calculations for the identification of stabile epitopes is expected to have a major impact on the future development of high affinity protein capturing binders.}, language = {en} } @article{CasertaZhangYarmanetal.2021, author = {Caserta, Giorgio and Zhang, Xiaorong and Yarman, Aysu and Supala, Eszter and Wollenberger, Ulla and Gyurcs{\´a}nyi, R{\´o}bert E. and Zebger, Ingo and Scheller, Frieder W.}, title = {Insights in electrosynthesis, target binding, and stability of peptide-imprinted polymer nanofilms}, series = {Electrochimica acta : the journal of the International Society of Electrochemistry (ISE)}, volume = {381}, journal = {Electrochimica acta : the journal of the International Society of Electrochemistry (ISE)}, publisher = {Elsevier}, address = {New York, NY [u.a.]}, issn = {0013-4686}, doi = {10.1016/j.electacta.2021.138236}, pages = {8}, year = {2021}, abstract = {Molecularly imprinted polymer (MIP) nanofilms have been successfully implemented for the recognition of different target molecules: however, the underlying mechanistic details remained vague. This paper provides new insights in the preparation and binding mechanism of electrosynthesized peptide-imprinted polymer nanofilms for selective recognition of the terminal pentapeptides of the beta-chains of human adult hemoglobin, HbA, and its glycated form HbA1c. To differentiate between peptides differing solely in a glucose adduct MIP nanofilms were prepared by a two-step hierarchical electrosynthesis that involves first the chemisorption of a cysteinyl derivative of the pentapeptide followed by electropolymerization of scopoletin. This approach was compared with a random single-step electrosynthesis using scopo-letin/pentapeptide mixtures. Electrochemical monitoring of the peptide binding to the MIP nanofilms by means of redox probe gating revealed a superior affinity of the hierarchical approach with a Kd value of 64.6 nM towards the related target. Changes in the electrosynthesized non-imprinted polymer and MIP nanofilms during chemical, electrochemical template removal and rebinding were substantiated in situ by monitoring the characteristic bands of both target peptides and polymer with surface enhanced infrared absorption spectroscopy. This rational approach led to MIPs with excellent selectivity and provided key mechanistic insights with respect to electrosynthesis, rebinding and stability of the formed MIPs.}, language = {en} } @article{LoewBogdanoffHerrmannetal.2006, author = {Loew, Noya and Bogdanoff, Peter and Herrmann, Iris and Wollenberger, Ursula and Scheller, Frieder W. and Katterle, Martin}, title = {Influence of modifications on the efficiency of pyrolysed CoTMPP as electrode material for horseradish peroxidase and the reduction of hydrogen peroxide}, series = {Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis}, volume = {18}, journal = {Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis}, number = {23}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1040-0397}, doi = {10.1002/elan.200603664}, pages = {2324 -- 2330}, year = {2006}, abstract = {A tailor-made horseradish peroxidase (HRP) bulk composite electrode was developed on the basis of pyrolyzed cobalt tetramethoxyphenylporphyrin (CoTMPP) by modifying pore size and surface area of the porous carbon material through varying amounts of iron oxalate and sulfur prior to pyrolyzation. The materials were used to immobilize horseradish peroxidase (HRP). These electrodes were characterized in terms of their efficiency to reduce hydrogen peroxide. The heterogeneous electron transfer rate constants of different materials were determined with the rotating disk electrode method and a k(S) (401 +/- 61 s(-1)) exceeding previously reported values for native HRP was found.}, language = {en} } @article{ButtermeyerPhilippMalletal.2002, author = {Buttermeyer, R. and Philipp, A. W. and Mall, J. W. and Ge, Bixia and Scheller, Frieder W. and Lisdat, Fred}, title = {In vivo measurement of oxygen derived free radicals during reperfusion injury}, year = {2002}, language = {en} } @article{SchellerBauerMakoweretal.2002, author = {Scheller, Frieder W. and Bauer, Christian G. and Makower, Alexander and Wollenberger, Ursula and Warsinke, Axel and Bier, Frank Fabian}, title = {Immunoassays using enzymatic amplification electrodes}, isbn = {0-7484-0791-X}, year = {2002}, language = {en} } @article{BeissenhirtzSchellerLisdat2003, author = {Beissenhirtz, Moritz Karl and Scheller, Frieder W. and Lisdat, Fred}, title = {Immobilized cytochrome c sensor in organic / aqueous media for the characterization of hydrophilic and hydrophobic antioxidants}, year = {2003}, language = {en} } @article{LettauGajovicEichelmannKwaketal.2004, author = {Lettau, Kristian and Gajovic-Eichelmann, N. and Kwak, Young-Keun and Scheller, Frieder W. and Warsinke, Axel}, title = {Hydroxylasen und katalytische Polymere f{\"u}r Biochips}, year = {2004}, language = {de} } @article{XieTangWollenbergeretal.1997, author = {Xie, B. and Tang, X. and Wollenberger, Ursula and Johansson, G. and Gorton, Lo and Scheller, Frieder W. and Danielsson, B.}, title = {Hybrid biosensor for simultaneous electrochemical and thermal detection}, year = {1997}, language = {en} } @article{BierEhrentreichFoersterBaueretal.1996, author = {Bier, Frank Fabian and Ehrentreich-F{\"o}rster, Eva and Bauer, Christian G. and Scheller, Frieder W.}, title = {High sensitive competitive immunodetection of 2,4-dichlorophenoxyacetic acid using enzymatic amplification with electrochemical detection}, year = {1996}, language = {en} } @article{SchellerYarmanBachmannetal.2014, author = {Scheller, Frieder W. and Yarman, Aysu and Bachmann, Till and Hirsch, Thomas and Kubick, Stefan and Renneberg, Reinhard and Schumacher, Soeren and Wollenberger, Ursula and Teller, Carsten and Bier, Frank Fabian}, title = {Future of biosensors: a personal view}, series = {Advances in biochemical engineering, biotechnology}, volume = {140}, journal = {Advances in biochemical engineering, biotechnology}, editor = {Gu, MB and Kim, HS}, publisher = {Springer}, address = {Berlin}, isbn = {978-3-642-54143-8; 978-3-642-54142-1}, issn = {0724-6145}, doi = {10.1007/10_2013_251}, pages = {1 -- 28}, year = {2014}, abstract = {Biosensors representing the technological counterpart of living senses have found routine application in amperometric enzyme electrodes for decentralized blood glucose measurement, interaction analysis by surface plasmon resonance in drug development, and to some extent DNA chips for expression analysis and enzyme polymorphisms. These technologies have already reached a highly advanced level and need minor improvement at most. The dream of the "100-dollar' personal genome may come true in the next few years provided that the technological hurdles of nanopore technology or of polymerase-based single molecule sequencing can be overcome. Tailor-made recognition elements for biosensors including membrane-bound enzymes and receptors will be prepared by cell-free protein synthesis. As alternatives for biological recognition elements, molecularly imprinted polymers (MIPs) have been created. They have the potential to substitute antibodies in biosensors and biochips for the measurement of low-molecular-weight substances, proteins, viruses, and living cells. They are more stable than proteins and can be produced in large amounts by chemical synthesis. Integration of nanomaterials, especially of graphene, could lead to new miniaturized biosensors with high sensitivity and ultrafast response. In the future individual therapy will include genetic profiling of isoenzymes and polymorphic forms of drug-metabolizing enzymes especially of the cytochrome P450 family. For defining the pharmacokinetics including the clearance of a given genotype enzyme electrodes will be a useful tool. For decentralized online patient control or the integration into everyday "consumables' such as drinking water, foods, hygienic articles, clothing, or for control of air conditioners in buildings and cars and swimming pools, a new generation of "autonomous' biosensors will emerge.}, language = {en} } @article{WollenbergerJinBernhardtetal.1998, author = {Wollenberger, Ursula and Jin, Wen and Bernhardt, Rita and Lehmann, Claudia and St{\"o}cklein, Walter F. M. and Brigelius-Floh{\´e}, Regina and Scheller, Frieder W.}, title = {Funktionalisierung von Elektroden f{\"u}r den direkten heterogenen Elektrotransfer}, year = {1998}, language = {de} } @article{TadjoungWaffoYesildagCasertaetal.2018, author = {Tadjoung Waffo, Armel Franklin and Yesildag, Cigdem and Caserta, Giorgio and Katz, Sagie and Zebger, Ingo and Lensen, Marga C. and Wollenberger, Ulla and Scheller, Frieder W. and Altintas, Zeynep}, title = {Fully electrochemical MIP sensor for artemisinin}, series = {Sensors and actuators : B, Chemical}, volume = {275}, journal = {Sensors and actuators : B, Chemical}, publisher = {Elsevier}, address = {Lausanne}, issn = {0925-4005}, doi = {10.1016/j.snb.2018.08.018}, pages = {163 -- 173}, year = {2018}, abstract = {This study aims to develop a rapid, sensitive and cost-effective biomimetic electrochemical sensor for artemisinin determination in plant extracts and for pharmacokinetic studies. A novel molecularly imprinted polymer (MIP)based electrochemical sensor was developed by electropolymerization of o-phenylenediamine (o-PD) in the presence of artemisinin on gold wire surface for sensitive detection of artemisinin. The experimental parameters, including selection of functional monomer, polymerization conditions, template extraction after polymerization, influence of pH and buffer were all optimized. Every step of imprinted film synthesis were evaluated by employing voltammetry techniques, surface-enhanced infrared absorption spectroscopy (SEIRAS) and atomic force microscopy (AFM). The specificity was further evaluated by investigating non-specific artemisinin binding on non-imprinted polymer (NIP) surfaces and an imprinting factor of 6.8 was achieved. The artemisinin imprinted polymers using o-PD as functional monomer have provided highly stable and effective binding cavities for artemisinin. Cross-reactivity studies with drug molecules showed that the MIPs are highly specific for artemisinin. The influence of matrix effect was further investigated both in artificial plant matrix and diluted human serum. The results revealed a high affinity of artemisinin-MIP with dissociation constant of 7.3 x 10(-9) M and with a detection limit of 0.01 mu M and 0.02 mu M in buffer and plant matrix, respectively.}, language = {en} } @article{SchellerWagener2004, author = {Scheller, Frieder W. and Wagener, C.}, title = {From gene to life}, year = {2004}, language = {en} } @article{BaeumnerGauglitzScheller2010, author = {Baeumner, Antje J. and Gauglitz, Guenter and Scheller, Frieder W.}, title = {Focus on bioanalysis}, issn = {1618-2642}, doi = {10.1007/s00216-010-4203-9}, year = {2010}, abstract = {Editoria}, language = {en} } @article{KleinjungBeierWarsinkeetal.1997, author = {Kleinjung, Frank and Beier, Frank F. and Warsinke, Axel and Scheller, Frieder W.}, title = {Fibre-optic genosensor for specific determination of femtomolar DNA oligomers}, year = {1997}, language = {en} } @article{LiuWollenbergerKatterleetal.2006, author = {Liu, Songqin and Wollenberger, Ursula and Katterle, Martin and Scheller, Frieder W.}, title = {Ferroceneboronic acid-based amperometric biosensor for glycated hemoglobin}, issn = {0925-4005}, doi = {10.1016/j.snb.2005.07.011}, year = {2006}, abstract = {An amperometric biosensor for the determination of glycated hemoglobin in human whole blood is proposed. The principle is based on the electrochemical measurement of ferroceneboronic acid (FcBA) that has been specifically bound to the glycated N-terminus. Hemoglobin is immobilized on a zirconium dioxide nanoparticle modified pyrolytic graphite electrode (PGE) in the presence of didodecyldimethylammonium bromide (DDAB). The incubation of this sensor in FcBA solution leads to the formation of an FcBA-modified surface due to the affinity interaction between boronate and the glycated sites of the hemoglobin. The binding of FcBA results in well-defined redox peaks with an E-0' of 0.299 V versus Ag/AgCl (1 M KCl). The square wave voltammetric response of the bound FcBA reflects the amount of glycated hemoglobin at the surface. This signal increases linearily with the degree of glycated hemoglobin from 6.8 to 14.0\% of total immobilized hemoglobin. The scheme was applied to the determination of the fraction of glycated hemoglobin in whole blood samples.}, language = {en} } @article{HalamekTellerMakoweretal.2006, author = {Halamek, Jan and Teller, Carsten and Makower, Alexander and Fournier, Didier and Scheller, Frieder W.}, title = {EQCN-based cholinesterase biosensors}, issn = {0013-4686}, doi = {10.1016/j.electacta.2006.03.047}, year = {2006}, abstract = {The binding of acetylcholinesterase (AChE) to a propidium-modified piezoelectric quartz crystal and its surface enzymatic activity have been investigated. Propidium binds to a site remote to the active center of AChE - the peripheral anionic site (PAS) - which is located on the rim of the gorge to the active site. The gold electrodes of the quartz crystal were first modified with 11-mercaptoundecanoic acid to which propidium was coupled. AChE binding was monitored by a quartz crystal nanobalance (QCN), followed by amperometric activity evaluation of the AChE loaded on the sensor. Interestingly, the binding is strong but does not inhibit AChE. However, an excess of propidium in solution inhibits the immobilized enzyme. The surface enzymatic activities observed depend on the amount of enzyme and differ according to the type and species, i.e. number of enzyme subunits (Electrophorus electricus tetrameric, Drosophila melanogaster mono- and dimeric form - DmAChE). The operational stability and regeneration, effect of propidium in solution and detection limit for substrate for various AChEs were investigated amperometrically.}, language = {en} } @article{SchellerMakowerBieretal.1995, author = {Scheller, Frieder W. and Makower, Alexander and Bier, Frank Fabian and Wollenberger, Ursula and Ghindilis, A. L. and Eremenko, A. V. and Pfeiffer, Dorothea}, title = {Enzymsensoren zur Bestimmung subnanomolarer Konzentrationen}, year = {1995}, language = {de} } @article{SchellerKirsteinSchubertetal.1993, author = {Scheller, Frieder W. and Kirstein, Dieter and Schubert, Florian and Pfeiffer, Dorothea and McNeil, C. J.}, title = {Enzymes in electrochemical biosensors}, year = {1993}, language = {en} } @article{StoeckleinScheller1997, author = {St{\"o}cklein, Walter F. M. and Scheller, Frieder W.}, title = {Enzymes and antibodies in organic media : analytical applications}, year = {1997}, language = {en} } @article{KaishevaIlievKazarevaetal.1996, author = {Kaisheva, A. and Iliev, I. and Kazareva, R. and Christov, S. and Wollenberger, Ursula and Scheller, Frieder W.}, title = {Enzyme/gas diffusion electrodes for determination of phenol}, year = {1996}, language = {en} } @article{SchellerMakowerGhindilisetal.1995, author = {Scheller, Frieder W. and Makower, Alexander and Ghindilis, A. L. and Bier, Frank Fabian and Ehrentreich-F{\"o}rster, Eva and Wollenberger, Ursula and Bauer, Christian G. and Micheel, Burkhard and Pfeiffer, Dorothea and Szeponik, Jan and Michael, N. and Kaden, H.}, title = {Enzyme sensors for subnanomolar concentrations}, year = {1995}, language = {en} } @article{StoeckleinMakowerBieretal.1997, author = {St{\"o}cklein, Walter F. M. and Makower, Alexander and Bier, Frank Fabian and Scheller, Frieder W.}, title = {Enzyme sensors and enzyme amplifification systems}, year = {1997}, language = {en} } @article{StoeckleinBehrsingScharteetal.2000, author = {St{\"o}cklein, Walter F. M. and Behrsing, Olaf and Scharte, Gudrun and Micheel, Burkhard and Benkert, Alexander and Sch{\"o}ssler, W. and Warsinke, Axel and Scheller, Frieder W.}, title = {Enzyme kinetic assays with surface plasmon resonance (BIAcore) based on competition between enzyme and creatinine antibody}, year = {2000}, language = {en} } @article{SchellerWollenberger2003, author = {Scheller, Frieder W. and Wollenberger, Ursula}, title = {Enzyme Electrodes}, isbn = {3-527-30401-0}, year = {2003}, language = {en} } @article{YarmanBadalyanGajovicEichelmannetal.2011, author = {Yarman, Aysu and Badalyan, Artavazd and Gajovic-Eichelmann, Nenad and Wollenberger, Ursula and Scheller, Frieder W.}, title = {Enzyme electrode for aromatic compounds exploiting the catalytic activities of microperoxidase-11}, series = {Biosensors and bioelectronics : the principal international journal devoted to research, design development and application of biosensors and bioelectronics}, volume = {30}, journal = {Biosensors and bioelectronics : the principal international journal devoted to research, design development and application of biosensors and bioelectronics}, number = {1}, publisher = {Elsevier}, address = {Oxford}, issn = {0956-5663}, doi = {10.1016/j.bios.2011.09.004}, pages = {320 -- 323}, year = {2011}, abstract = {Microperoxidase-11 (MR-11) which has been immobilised in a matrix of chitosan-embedded gold nanoparticles on the surface of a glassy carbon electrode catalyzes the conversion of aromatic substances. This peroxide-dependent catalysis of microperoxidase has been applied in an enzyme electrode for the first time to indicate aromatic compounds such as aniline. 4-fluoroaniline, catechol and p-aminophenol. The electrode signal is generated by the cathodic reduction of the quinone or quinoneimine which is formed in the presence of both MP-II and peroxide from the substrate. The same sensor principle will be extended to aromatic drugs.}, language = {en} } @article{SchellerPfeifferLisdatetal.1998, author = {Scheller, Frieder W. and Pfeiffer, Dorothea and Lisdat, Fred and Bauer, Christian G. and Gajovic, Nenad}, title = {Enzyme biosensors based on oxygen detection}, year = {1998}, language = {en} } @article{WollenbergerNeumannRiedeletal.1994, author = {Wollenberger, Ursula and Neumann, B. and Riedel, K. and Scheller, Frieder W.}, title = {Enzyme and microbial sensors for phosphate, phenols, pesticides and peroxides}, year = {1994}, language = {en} } @article{WollenbergerNeumannScheller1993, author = {Wollenberger, Ursula and Neumann, B. and Scheller, Frieder W.}, title = {Enzyme and microbial sensors for environmental Monitoring}, year = {1993}, language = {en} } @article{WollenbergerScheller1993, author = {Wollenberger, Ursula and Scheller, Frieder W.}, title = {Enzyme activation for activator and enzyme activity measurement}, year = {1993}, language = {en} } @article{SchellerPfeifferSchubertetal.1995, author = {Scheller, Frieder W. and Pfeiffer, Dorothea and Schubert, Florian and Wollenberger, Ursula}, title = {Enzyme - based electrodes}, year = {1995}, language = {en} } @article{WollenbergerLisdatScheller1997, author = {Wollenberger, Ursula and Lisdat, Fred and Scheller, Frieder W.}, title = {Enzymatic substrade recycling electrodes}, year = {1997}, language = {en} } @article{WollenbergerSchubertPfeifferetal.1993, author = {Wollenberger, Ursula and Schubert, Florian and Pfeiffer, Dorothea and Scheller, Frieder W.}, title = {Enhancing biosensor performance using multienzyme systems}, year = {1993}, language = {en} } @article{NeumannGoetzWrzoleketal.2018, author = {Neumann, Bettina and G{\"o}tz, Robert and Wrzolek, Pierre and Scheller, Frieder W. and Weidinger, Inez M. and Schwalbe, Matthias and Wollenberger, Ulla}, title = {Enhancement of the Electrocatalytic Activity of Thienyl-Substituted Iron Porphyrin Electropolymers by a Hangman Effect}, series = {ChemCatChem : heterogeneous \& homogeneous \& bio- \& nano-catalysis ; a journal of ChemPubSoc Europe}, volume = {10}, journal = {ChemCatChem : heterogeneous \& homogeneous \& bio- \& nano-catalysis ; a journal of ChemPubSoc Europe}, number = {19}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1867-3880}, doi = {10.1002/cctc.201800934}, pages = {4353 -- 4361}, year = {2018}, abstract = {The thiophene-modified iron porphyrin FeT3ThP and the respective iron Hangman porphyrin FeH3ThP, incorporating a carboxylic acid hanging group in the second coordination sphere of the iron center, were electropolymerized on glassy carbon electrodes using 3,4-ethylenedioxythiophene (EDOT) as co-monomer. Scanning electron microscopy images and Resonance Raman spectra demonstrated incorporation of the porphyrin monomers into a fibrous polymer network. Porphyrin/polyEDOT films catalyzed the reduction of molecular oxygen in a four-electron reaction to water with onset potentials as high as +0.14V vs. Ag/AgCl in an aqueous solution of pH7. Further, FeT3ThP/polyEDOT films showed electrocatalytic activity towards reduction of hydrogen peroxide at highly positive potentials, which was significantly enhanced by introduction of the carboxylic acid hanging group in FeH3ThP. The second coordination sphere residue promotes formation of a highly oxidizing reaction intermediate, presumably via advantageous proton supply, as observed for peroxidases and catalases making FeH3ThP/polyEDOT films efficient mimics of heme enzymes.}, language = {en} } @article{BeissenhirtzSchellerViezzolietal.2006, author = {Beissenhirtz, Moritz Karl and Scheller, Frieder W. and Viezzoli, Maria Silvia and Lisdat, Fred}, title = {Engineered superoxide dismutase monomers for superoxide biosensor applications}, issn = {0003-2700}, doi = {10.1021/Ac051465g}, year = {2006}, abstract = {Because of its high reaction rate and specificity, the enzyme superoxide dismutase (SOD) offers great potential for the sensitive quantification of superoxide radicals in electrochemical biosensors. In this work, monomeric mutants of human Cu,Zn-SOD were engineered to contain one or two additional cysteine residues, which could be used to bind the protein to gold surfaces, thus making the use of promotor molecules unnecessary. Six mutants were successfully designed, expressed, and purified. All mutants bound directly to unmodified gold surfaces via the sulfur of the cysteine residues and showed a quasireversible, direct electron transfer to the electrode. Thermodynamic and kinetic parameters of the electron transfer were characterized and showed only slight variations between the individual mutants. For one of the mutants, the interaction with the superoxide radical was studied in more detail. For both partial reactions of the dismutation, an interaction between protein and radical could be shown. In an amperometric biosensorial approach, the SOD-mutant electrode was successfully applied for the detection of superoxide radicals. In the oxidation region, the electrode surpassed the sensitivity of the commonly used cytochrome c electrodes by similar to 1 order of magnitude while not being limited by interferences, but the electrode did not fully reach the sensitivity of dimeric Cu,Zn-SOD immobilized on MPA-modified gold}, language = {en} } @article{KirsteinKirsteinSchelleretal.1994, author = {Kirstein, Dieter and Kirstein, Lincoln and Scheller, Frieder W. and Dieckmann, St. and Ronnenberg, J. and Beckmann, Dieter and Weckenbrock, E.}, title = {Elektroenzymatische Reduktion von Nitrat}, year = {1994}, language = {de} } @article{WollenbergerBistolasJungetal.2004, author = {Wollenberger, Ursula and Bistolas, Nikitas and Jung, Christiane and Shumyantseva, V. V. and Ruzgas, T. and Scheller, Frieder W.}, title = {Elektroden-Design f{\"u}r elektronische Wechselwirkung mit Monooxygenasen}, isbn = {3-8047-2132-x}, year = {2004}, language = {de} } @article{StojanovicErdossyKeltaietal.2017, author = {Stojanovic, Zorica and Erdossy, Julia and Keltai, Katalin and Scheller, Frieder W. and Gyurcsanyi, Robert E.}, title = {Electrosynthesized molecularly imprinted polyscopoletin nanofilms for human serum albumin detection}, series = {Analytica chimica acta : an international journal devoted to all branches of analytical chemistry}, volume = {977}, journal = {Analytica chimica acta : an international journal devoted to all branches of analytical chemistry}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0003-2670}, doi = {10.1016/j.aca.2017.04.043}, pages = {1 -- 9}, year = {2017}, abstract = {Molecularly imprinted polymers (MIPs) rendered selective solely by the imprinting with protein templates lacking of distinctive properties to facilitate strong target-MIP interaction are likely to exhibit medium to low template binding affinities. While this prohibits the use of such MIPs for applications requiring the assessment of very low template concentrations, their implementation for the quantification of high-abundance proteins seems to have a clear niche in the analytical practice. We investigated this opportunity by developing a polyscopoletin-based MIP nanofilm for the electrochemical determination of elevated human serum albumin (HSA) in urine. As reference for a low abundance protein ferritin-MIPs were also prepared by the same procedure. Under optimal conditions, the imprinted sensors gave a linear response to HSA in the concentration range of 20-100 mg/dm(3), and to ferritin in the range of 120-360 mg/dm(3). While as expected the obtained limit of detection was not sufficient to determine endogenous ferritin in plasma, the HSA-sensor was successfully employed to analyse urine samples of patients with albuminuria. The results suggest that MIP-based sensors may be applicable for quantifying high abundance proteins in a clinical setting. (c) 2017 Elsevier B.V. All rights reserved.}, language = {en} } @article{ZhangYarmanErdossyetal.2018, author = {Zhang, Xiaorong and Yarman, Aysu and Erdossy, Julia and Katz, Sagie and Zebger, Ingo and Jetzschmann, Katharina J. and Altintas, Zeynep and Wollenberger, Ulla and Gyurcsanyi, Robert E. and Scheller, Frieder W.}, title = {Electrosynthesized MIPs for transferrin}, series = {Biosensors and bioelectronics : the principal international journal devoted to research, design development and application of biosensors and bioelectronics}, volume = {105}, journal = {Biosensors and bioelectronics : the principal international journal devoted to research, design development and application of biosensors and bioelectronics}, publisher = {Elsevier}, address = {Oxford}, issn = {0956-5663}, doi = {10.1016/j.bios.2018.01.011}, pages = {29 -- 35}, year = {2018}, abstract = {Molecularly imprinted polymer (MP) nanofilrns for transferrin (Trf) have been synthesized on gold surfaces by electro-polymerizing the functional monomer scopoletin in the presence of the protein target or around pre-adsorbed Trf. As determined by atomic force microscopy (AFM) the film thickness was comparable with the molecular dimension of the target. The target (re)binding properties of the electro-synthesized MIP films was evaluated by cyclic voltammetry (CV) and square wave voltammetry (SWV) through the target-binding induced permeability changes of the MIP nanofilms to the ferricyanide redox marker, as well as by surface plasmon resonance (SPR) and surface enhanced infrared absorption spectroscopy (SEIRAS) of the immobilized protein molecules. For Trf a linear concentration dependence in the lower micromolar range and an imprinting factor of similar to 5 was obtained by SWV and SPR. Furthermore, non-target proteins including the iron-free apo-Trf were discriminated by pronounced size and shape specificity. Whilst it is generally assumed that the rebinding of the target or of cross-reacting proteins exclusively takes place at the polymer here we considered also the interaction of the protein molecules with the underlying gold transducers. We demonstrate by SWV that adsorption of proteins suppresses the signal of the redox marker even at the bare gold surface and by SEIRAS that the treatment of the MIP with proteinase K or NaOH only partially removes the target protein. Therefore, we conclude that when interpreting binding of proteins to directly MIP-covered gold electrodes the interactions between the protein and the gold surface should also be considered.}, language = {en} } @article{LeiWollenbergerBistolasetal.2002, author = {Lei, Chenghong and Wollenberger, Ursula and Bistolas, Nikitas and Guiseppi-Eli, A. and Scheller, Frieder W.}, title = {Electron transfer of hemoglobin at electrodes modified with colloidal clay nanoparticles}, year = {2002}, language = {en} } @article{GeSchellerLisdat2003, author = {Ge, Bixia and Scheller, Frieder W. and Lisdat, Fred}, title = {Electrochemistry of immobilized CuZnSOD and FeSOD and their interaction with superoxide radicals}, year = {2003}, abstract = {Copper, zinc superoxide dismutase (CuZnSOD) from bovine erythrocytes and iron superoxide dismutase from Escherichia coli (FeSOD) were immobilized on 3-mercaptopropionic acid (MPA)-modified gold electrodes, respectively. The characterization of the SOD electrodes showed a quasi-reversible, electrochemical redox behavior with a formal potential of 47 {\~n} 4 mV and -154 {\~n} 5 mV (vs. Ag/AgCl, 1 M KCl) for surface adsorbed CuZnSOD and FeSOD, respectively. The heterogeneous electron transfer rate constants were determined to be about 65 and 35/s, respectively. Covalent fixation of both SODs was also feasible with only slight changes in the formal potential. The interaction of superoxide radicals (O2-) with the SOD electrode was investigated. No catalytic current could be observed. However, due to the fast cyclic reaction of SOD with superoxide, the communication of the protein with the electrode was strongly influenced. The amperometric detection of superoxide radicals is discussed.}, language = {en} } @article{KatterleWollenbergerScheller1997, author = {Katterle, Martin and Wollenberger, Ursula and Scheller, Frieder W.}, title = {Electrochemistry of hemoglobin at modified silver electrodes is not a redox-process of iron protoporhyrin IX}, year = {1997}, language = {en} } @article{JuLiuGeetal.2000, author = {Ju, Huangxian and Liu, Songqin and Ge, Bixia and Lisdat, Fred and Scheller, Frieder W.}, title = {Electrochemistry of cytochrome c immobilized on colloidal gold modified carbon paste electrodes and its electrocatalytic activity}, year = {2000}, language = {en} } @article{PfeifferSchubertWollenbergeretal.1996, author = {Pfeiffer, Dorothea and Schubert, Frank and Wollenberger, Ursula and Scheller, Frieder W.}, title = {Electrochemical sensors : enzyme electrodes and field effect transistors}, year = {1996}, language = {en} } @article{WelzelKossmehlEngelmannetal.1997, author = {Welzel, H.-P. and Kossmehl, G. and Engelmann, G. and Neumann, B. and Wollenberger, Ursula and Scheller, Frieder W.}, title = {Electrochemical polymerization of functionalized thiohene derivatives for immobilization of proteins}, year = {1997}, language = {en} } @article{KulysKrikstopaitisSchelleretal.2004, author = {Kulys, J. and Krikstopaitis, K. and Scheller, Frieder W. and Wollenberger, Ursula}, title = {Electrochemical parameters of phenoxazine derivatives in solution and at monolayer-modified gold electrodes}, year = {2004}, abstract = {Electrochemical properties of beta-(10-phenoxazinyl) propylamine (APPX) and beta-(10-phenoxazinyl) propionic acid (PPX) have been studied in solution, and in immobilized state on gold electrodes modified with monolayers of cystamine and mercaptoundecanoic acid. A reversible diffusion-controlled process of APPX and PPX was observed at a bare gold electrode. The electrochemical conversion of both compounds at modified gold electrodes was a quasireversible diffusion-controlled process. The redox potential of immobilized APPX (443 mV) was similar to the potential in solution, while the value of the immobilized PPX was 131 mV higher than in solution. The immobilized mediators were electrocatalytically active in the fungal peroxidase-catalyzed hydrogen peroxide reduction}, language = {en} } @article{OzcelikayKurbanogluZhangetal.2019, author = {Ozcelikay, Goksu and Kurbanoglu, Sevinc and Zhang, Xiaorong and S{\"o}z, {\c{C}}ağla Kosak and Wollenberger, Ulla and Ozkan, Sibel A. and Yarman, Aysu and Scheller, Frieder W.}, title = {Electrochemical MIP Sensor for Butyrylcholinesterase}, series = {Polymers}, volume = {11}, journal = {Polymers}, number = {12}, publisher = {MDPI}, address = {Basel}, issn = {2073-4360}, doi = {10.3390/polym11121970}, pages = {11}, year = {2019}, abstract = {Molecularly imprinted polymers (MIPs) mimic the binding sites of antibodies by substituting the amino acid-scaffold of proteins by synthetic polymers. In this work, the first MIP for the recognition of the diagnostically relevant enzyme butyrylcholinesterase (BuChE) is presented. The MIP was prepared using electropolymerization of the functional monomer o-phenylenediamine and was deposited as a thin film on a glassy carbon electrode by oxidative potentiodynamic polymerization. Rebinding and removal of the template were detected by cyclic voltammetry using ferricyanide as a redox marker. Furthermore, the enzymatic activity of BuChE rebound to the MIP was measured via the anodic oxidation of thiocholine, the reaction product of butyrylthiocholine. The response was linear between 50 pM and 2 nM concentrations of BuChE with a detection limit of 14.7 pM. In addition to the high sensitivity for BuChE, the sensor responded towards pseudo-irreversible inhibitors in the lower mM range.}, language = {en} } @article{JinWollenbergerKaergeletal.1997, author = {Jin, Wen and Wollenberger, Ursula and K{\"a}rgel, E. and Schunck, W.-H. and Scheller, Frieder W.}, title = {Electrochemical investigation of the intermolecular electron transfer between cytochrome c and NADPH-cytochrome P450-reductase}, year = {1997}, language = {en} } @article{FridmanWollenbergerBogdanovskayaetal.2000, author = {Fridman, Vadim and Wollenberger, Ursula and Bogdanovskaya, V. A. and Lisdat, Fred and Ruzgas, T. and Lindgren, A. and Gorton, Lo and Scheller, Frieder W.}, title = {Electrochemical investigation of cellobiose oxidation by cellobiose dehydrogenase in the presence of cytochrome c as mediator}, year = {2000}, language = {en} } @article{WarsinkeBenkertScheller2000, author = {Warsinke, Axel and Benkert, Alexander and Scheller, Frieder W.}, title = {Electrochemical immunoassays}, year = {2000}, language = {en} }