TY  - JOUR
A1  - Zhang, Xiaorong
A1  - Caserta, Giorgio
A1  - Yarman, Aysu
A1  - Supala, Eszter
A1  - Tadjoung Waffo, Armel Franklin
A1  - Wollenberger, Ulla
A1  - Gyurcsanyi, Robert E.
A1  - Zebger, Ingo
A1  - Scheller, Frieder W.
T1  - "Out of Pocket" protein binding
BT  - a dilemma of epitope imprinted polymers revealed for human hemoglobin
JF  - Chemosensors
N2  - The epitope imprinting approach applies exposed peptides as templates to synthesize Molecularly Imprinted Polymers (MIPs) for the recognition of the parent protein. While generally the template protein binding to such MIPs is considered to occur via the epitope-shaped cavities, unspecific interactions of the analyte with non-imprinted polymer as well as the detection method used may add to the complexity and interpretation of the target rebinding. To get new insights on the effects governing the rebinding of analytes, we electrosynthesized two epitope-imprinted polymers using the N-terminal pentapeptide VHLTP-amide of human hemoglobin (HbA) as the template. MIPs were prepared either by single-step electrosynthesis of scopoletin/pentapeptide mixtures or electropolymerization was performed after chemisorption of the cysteine extended VHLTP peptide. Rebinding of the target peptide and the parent HbA protein to the MIP nanofilms was quantified by square wave voltammetry using a redox probe gating, surface enhanced infrared absorption spectroscopy, and atomic force microscopy. While binding of the pentapeptide shows large influence of the amino acid sequence, all three methods revealed strong non-specific binding of HbA to both polyscopoletin-based MIPs with even higher affinities than the target peptides.
KW  - Molecularly Imprinted Polymers
KW  - epitope imprinting
KW  - non-specific
KW  - binding
KW  - redox gating
KW  - SEIRA spectroelectrochemistry
Y1  - 2021
U6  - https://doi.org/10.3390/chemosensors9060128
SN  - 2227-9040
VL  - 9
IS  - 6
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Huang, T.
A1  - Warsinke, Axel
A1  - Koroljova-Skorobogatko, O. V.
A1  - Makower, Alexander
A1  - Kuwana, T.
A1  - Scheller, Frieder W.
T1  - A bienzyme carbon paste electrode for the sensitive detection of NADPH and the measurement of glucose-6- phosphate dehydrogenase
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Gajovic, Nenad
A1  - Warsinke, Axel
A1  - Scheller, Frieder W.
T1  - A bienzyme electrode for L-malate based on a novel and general design
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Eremenko, A. V.
A1  - Makower, Alexander
A1  - Bauer, Christian G.
A1  - Kurochkin, I. N.
A1  - Scheller, Frieder W.
T1  - A bienzyme electrode for tyrosine containing peptides determination
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Lettau, Kristian
A1  - Warsinke, Axel
A1  - Katterle, Martin
A1  - Danielsson, Bengt
A1  - Scheller, Frieder W.
T1  - A bifunctional molecularly imprinted polymer (MIP): analysis of binding and catalysis by a thermistor
N2  - Binding or catalysis? Both can be distinguished with a molecularly imprinted polymer (MIP) by the different patterns of heat generation. The catalytically active sites, like in the corresponding enzyme, generate a steady-state temperature increase. Thus, enzyme-like catalysis and antibody-analogue binding are analyzed simultaneously in a bifunctional MIP for the first time (see scheme).
Y1  - 2006
UR  - http://www3.interscience.wiley.com/cgi-bin/jhome/26737/
U6  - https://doi.org/10.1002/anie.200601796
ER  - 
TY  - JOUR
A1  - Chen, Ziping
A1  - Warsinke, Axel
A1  - Gajovic, Nenad
A1  - Große, St.
A1  - Hu, J.
A1  - Kleber, H.-P.
A1  - Scheller, Frieder W.
T1  - A D-carnitine dehydrogenase electrode for the assessment of enantiomeric purity of L-carnitine preparations
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Song, Min Ik
A1  - Bier, Frank Fabian
A1  - Scheller, Frieder W.
T1  - A method to detect superoxide radicals using teflon membrane and superoxide dismutase
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Gajovic, Nenad
A1  - Warsinke, Axel
A1  - Scheller, Frieder W.
T1  - A novel multienzyme electrode for the determination of citrate
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Teller, C.
A1  - Halamek, Jan
A1  - Makower, Alexander
A1  - Fournier, Didier
A1  - Schulze, H.
A1  - Scheller, Frieder W.
T1  - A piezoelectric sensor with propidium as a recognition element for cholinesterases
N2  - A piezoelectric biosensor has been developed on the basis of the reversible acetylcholinesterase (AChE) inhibitor propidium. The propidium cation was bound to a 11-mercaptoundecanoic acid monolayer on gold-coated quartz crystals. The immobilization was done via activation of carboxyl groups by 1,3-dicyclohexylcarbodiimide (DCC). Different types of cholinesterases (acetyl- and butyryl-ChE) from different origins were tested for their binding ability towards the immobilized propidium. Binding Studies were performed in a flow system, Furthermore, catalytically active and organophosphate-inhibited enzyme were compared re-aiding their binding capability. The binding constants were derived by using an one to one binding model and a refined model also including rebinding effects. It was shown that organophosphorylation of the active site hardly influences the affinity of AChE towards propidium. Furthermore the propidium-based biosensor provides equal sensitivity as compared with piezolelectric sensors with immobilized paraoxon- an active site ligand of AChE. (c) 2005 Elsevier B.V. All rights reserved
Y1  - 2006
U6  - https://doi.org/10.1016/j.snb.2005.02.053
ER  - 
TY  - JOUR
A1  - Gajovic, Nenad
A1  - Habermüller, K.
A1  - Warsinke, Axel
A1  - Schuhmann, W.
A1  - Scheller, Frieder W.
T1  - A pyruvate oxidase electrode based on an electrochemically deposited redox polymer
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Bier, Frank Fabian
A1  - Ehrentreich-Förster, Eva
A1  - Dölling, R.
A1  - Eremenko, A. V.
A1  - Scheller, Frieder W.
T1  - A redox-label immunosensor on basis of a bi-enzyme electrode
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Beissenhirtz, Moritz Karl
A1  - Scheller, Frieder W.
A1  - Lisdat, Fred
T1  - A superoxide sensor based on a multilayer cytochrome c electrode
N2  - 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
Y1  - 2004
SN  - 0003-2700
ER  - 
TY  - JOUR
A1  - Scheller, Frieder W.
A1  - Schmid, Rolf
T1  - A tribute to Isao Karube (1942-2020) and his influence on sensor science
JF  - Analytical and bioanalytical chemistry : a merger of Fresenius' journal of analytical chemistry, Analusis and Quimica analitica
KW  - Karube
KW  - Japan
KW  - biosensors
KW  - lifetime achievements
Y1  - 2020
U6  - https://doi.org/10.1007/s00216-020-02946-5
SN  - 1618-2642
SN  - 1618-2650
VL  - 412
IS  - 28
SP  - 7709
EP  - 7711
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Stoellner, Daniela
A1  - Scheller, Frieder W.
A1  - Warsinke, Axel
T1  - Activation of cellulose membranes with 1,1ï-carbonyldiimidazole or 1-cyano-4-4-dimethylaminopyridinium tetrafluoroborate as a basis for the development of immunosensors
Y1  - 2002
ER  - 
TY  - JOUR
A1  - Makower, Alexander
A1  - Barmin, Anatoli V.
A1  - Morzunova, T.
A1  - Eremenko, Arkadi V.
A1  - Bier, Frank Fabian
A1  - Scheller, Frieder W.
T1  - Affinity enzymomoetric assay for detection of organophosphorus compounds
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Liu, Songqin
A1  - Wollenberger, Ursula
A1  - Halamek, Jan
A1  - Leupold, Eik
A1  - Stöcklein, Walter F. M.
A1  - Warsinke, Axel
A1  - Scheller, Frieder W.
T1  - Affinity interaction betwen phenylboronic acid-carrying self-assembled monolayers and FAD or HRP
N2  - A method is provided for the recognition of glycated molecules based on their binding affinities to boronate- carrying monolayers. The affinity interaction of flavin adenine dinucleotide (FAD) and horseradish peroxidase (HRP) with phenylboronic acid monolayers on gold was investigated by using voltammetric and microgravimetric methods. Conjugates of 3-aminopherrylboronic acid and 3,3'-dithiodipropionic acid di(N-hydroxysuccinimide ester) or 11-mercaptoundecanoic acid were prepared and self-assembled on gold surfaces to generate monolayers. FAD is bound to this modified sur-face and recognized by a pair of redox peaks with a formal potential of -0.433 V in a 0.1 m phosphate buffer solution, pH 6.5. Upon addition of a sugar to the buffer, the bound FAD could be replaced, indicating that the binding is reversible. Voltammetric, mass measurements, and photometric activity assays show that the HRP can also be bound to the interface. This binding is reversible, and HRP can be replaced by sorbitol or removed in acidic solution. The effects of pH, incubation time, and concentration of H2O2 were studied by comparing the catalytic reduction of H2O2 in the presence of the electron-donor thionine. The catalytic current of the HRP-loaded electrode was proportional to HRP concentrations in the incubation solution in the range between 5 mu g mL(-1) and 0.4 mg mL(-1) with a linear slope of 3.34 mu A mL mg(-1) and a correlation coefficient of 0.9945
Y1  - 2005
ER  - 
TY  - JOUR
A1  - Ignatov, S.
A1  - Shishniashvili, D.
A1  - Ge, Bixia
A1  - Scheller, Frieder W.
A1  - Lisdat, Fred
T1  - Amperometric biosensor based on a functionalized gold electrode for the detection of antioxidants
Y1  - 2002
ER  - 
TY  - JOUR
A1  - Pfeiffer, Dorothea
A1  - Scheller, Frieder W.
A1  - Schubert, Florian
A1  - Setz, K.
T1  - Amperometric enzyme electrodes for lactate and glucose determinations in highly diluted and undiluted media
Y1  - 1993
ER  - 
TY  - JOUR
A1  - Iliev, I.
A1  - Kaisheva, A.
A1  - Scheller, Frieder W.
A1  - Pfeiffer, Dorothea
T1  - Amperometric gas-diffusion / enzyme electrode
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Kirstein, Dieter
A1  - Kirstein, Lincoln
A1  - Scheller, Frieder W.
A1  - Borcherding, H.
T1  - Amperometric nitrate biosensors on the basis of Pseudomonas stutzeri nitrate reductase
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Bier, Frank Fabian
A1  - Ehrentreich-Förster, Eva
A1  - Scheller, Frieder W.
T1  - Amplifying bienzyme cycle-linked immunoassays for determination of 2,4- dichlorphenoxyacetic acid
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Mak, Karen K. W.
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
A1  - Renneberg, Reinhard
T1  - An amperometric bi-enzyme sensor for determination of formate using cofactor regeneration
Y1  - 2003
ER  - 
TY  - JOUR
A1  - Bier, Frank Fabian
A1  - Ehrentreich-Förster, Eva
A1  - Makower, Alexander
A1  - Scheller, Frieder W.
T1  - An enzymatic amplification cycle for high sensitive immunoassay
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Lettau, Kristian
A1  - Warsinke, Axel
A1  - Laschewsky, André
A1  - Mosbach, K.
A1  - Yilmaz, E.
A1  - Scheller, Frieder W.
T1  - An esterolytic imprinted polymer prepared via a silica-supported transition state analogue
N2  - In this work we describe a new preparation method for an esterolytic imprinted polymer with catalytic sites on the surface. A template was prepared by immobilizing a transition state analogue (phosphoramidic acid derivative) of an esterolytic reaction within porous silica particles. Polymerization within the pores was carried out using 4- vinylimidazole as a functional monomer and divinylbenzene as a cross-linker. The polymer was released by dissolution of the silica support with hydrofluoric acid and catalytic properties were studied by incubation with three different 4- nitrophenylesters and spectrophotometric determination of the released 4-nitrophenol. For 4-nitrophenyl acetate an activity of 211 nmol min(-1) mg(-1) and a K-m value of 2.2 mmol L-1 was obtained
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Lisdat, Fred
A1  - Utepbergenov, D.
A1  - Haseloff, R. F.
A1  - Blasig, Ingolf E.
A1  - Stöcklein, Walter F. M.
A1  - Scheller, Frieder W.
A1  - Brigelius-Flohé, Regina
T1  - An optical method for the detection of oxidative stress using protein-RNA interaction
Y1  - 2001
ER  - 
TY  - JOUR
A1  - Scheller, Frieder W.
A1  - Bier, Frank Fabian
T1  - Analytical Biochemistry (Editorial)
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Streffer, Katrin
A1  - Kaatz, Helvi
A1  - Bauer, Christian G.
A1  - Makower, Alexander
A1  - Schulmeister, Thomas
A1  - Scheller, Frieder W.
A1  - Peter, Martin G.
A1  - Wollenberger, Ursula
T1  - Application of a sensitive catechol detector for determination of tyrosinase inhibitors
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Scheller, Frieder W.
A1  - Lisdat, Fred
A1  - Wollenberger, Ursula
T1  - Application of electrically contacted enzymes for biosensors
Y1  - 2005
SN  - 3-527- 30690-0
ER  - 
TY  - JOUR
A1  - Ozcelikay, Goksu
A1  - Kurbanoglu, Sevinc
A1  - Yarman, Aysu
A1  - Scheller, Frieder W.
A1  - Ozkan, Sibel A.
T1  - Au-Pt nanoparticles based molecularly imprinted nanosensor for electrochemical detection of the lipopeptide antibiotic drug Daptomycin
JF  - Sensors and actuators : B, Chemical
N2  - In this work, a novel electrochemical molecularly imprinted polymer (MIP) sensor for the detection of the lipopeptide antibiotic Daptomycin (DAP) is presented which integrates gold decorated platinum nanoparticles (Au-Pt NPs) into the nanocomposite film. The sensor was prepared by electropolymerization of o-phenylenediamine (o-PD) in the presence of DAP using cyclic voltammetry. Cyclic voltammetry and differential pulse voltammetry were applied to follow the changes in the MIP-layer related to rebinding and removal of the target DAP by using the redox marker [Fe(CN)(6)](3-/4-). Under optimized operational conditions, the MIP/Au-Pt NPs/ GCE nanosensor exhibits a linear response in the range of 1-20 pM towards DAP. The limit of detection and limit of quantification were determined to be 0.161pM +/- 0.012 and 0.489pM +/- 0.012, respectively. The sensitivity towards the antibiotics Vancomycin and Erythromycin and the amino acids glycine and tryptophan was below 7 percent as compared with DAP. Moreover, the nanosensor was also successfully used for the detection of DAP in deproteinated human serum samples.
KW  - molecularly imprinted polymer
KW  - Daptomycin
KW  - platinum nanoparticles
KW  - gold
KW  - nanoparticles
KW  - modified electrodes
Y1  - 2020
U6  - https://doi.org/10.1016/j.snb.2020.128285
SN  - 0925-4005
VL  - 320
PB  - Elsevier Science
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Bauer, Christian G.
A1  - Eremenko, A. V.
A1  - Kühn, A.
A1  - Kürzinger, K.
A1  - Markower, Alexander
A1  - Scheller, Frieder W.
T1  - Automated amplifield flow immunoassay for cocaine
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Jetzschmann, Katharina J.
A1  - Tank, Steffen
A1  - Jagerszki, Gyula
A1  - Gyurcsanyi, Robert E.
A1  - Wollenberger, Ulla
A1  - Scheller, Frieder W.
T1  - Bio-Electrosynthesis of Vectorially Imprinted Polymer Nanofilms for Cytochrome P450cam
JF  - ChemElectroChem
N2  - A new approach for synthesizing a vectorially imprinted polymer (VIP) is presented for the microbial cytochrome P450cam enzyme. A surface attached binding motif of a natural reaction partner of the target protein, putidaredoxin (Pdx), is the anchor to the underlying transducer. The 15 amino acid peptide anchor, which stems from the largest continuous amino acid chain within the binding site of Pdx was modified: (i) internal cysteines were replaced by serines to prevent disulfide bond formation; (ii) 2 ethylene glycol units were attached to the N-terminus as a spacer region; and (iii) an N-terminal cysteine was added to allow the immobilization on the gold electrode surface. Immobilization on GCE was achieved via an N-(1-pyrenyl)maleimide (NPM) cross-linker. In this way oriented immobilization of P450cam was accomplished by binding it to a peptide-modified gold or glassy carbon electrode (GCE) prior to the electrosynthesis of a polymer nanofilm around the immobilized target. This VIP nanofilm enabled reversible oriented docking of P450cam as it is indicated by the catalytic oxygen reduction via direct electron transfer between the enzyme and the underlying electrode. Catalysis of oxygen reduction by P450cam bound to the VIP-modified GCE was used to measure rebinding to the VIP. The mild coupling of an oxidoreductase with the electrode may be appropriate for realizing electrode-driven substrate conversion by instable P450 enzymes without the need of NADPH co-factor.
KW  - cytochrome P450
KW  - direct electron transfer
KW  - electropolymerization
KW  - molecularly imprinted polymers
KW  - protein imprinting
Y1  - 2019
U6  - https://doi.org/10.1002/celc.201801851
SN  - 2196-0216
VL  - 6
IS  - 6
SP  - 1818
EP  - 1823
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Lehmann, Claudia
A1  - Wollenberger, Ursula
A1  - Brigelius-Flohé, Regina
A1  - Scheller, Frieder W.
T1  - Bioelectrocatalysis by a selenoenzyme
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Bogdanovskaya, V. A.
A1  - Fridman, Vadim
A1  - Tarasevich, M. R.
A1  - Scheller, Frieder W.
T1  - Bioelectrocatalysis by immobilized peroxidase : the reaction mechanism and the possibility of electroanalytical detection of both inhibitors and activators of enzyme
Y1  - 1994
ER  - 
TY  - JOUR
A1  - Yarman, Aysu
A1  - Nagel, Thomas
A1  - Gajovic-Eichelmann, Nenad
A1  - Fischer, Anna
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
T1  - Bioelectrocatalysis by Microperoxidase-11 in a Multilayer Architecture of Chitosan Embedded Gold Nanoparticles
JF  - Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis
N2  - We report on the redox behaviour of the microperoxidase-11 (MP-11) which has been electrostatically immobilized in a matrix of chitosan-embedded gold nanoparticles on the surface of a glassy carbon electrode. MP-11 contains a covalently bound heme c as the redox active group that exchanges electrons with the electrode via the gold nanoparticles. Electroactive surface concentration of MP-11 at high scan rate is between 350+/-50 pmol cm(-2), which reflects a multilayer process. The formal potential (E degrees') of MP-11 in the gold nanoparticles-chitosan film was estimated to be -(267.7+/-2.9) mV at pH 7.0. The heterogeneous electron transfer rate constant (k(s)) starts at 1.21 s(-1) and levels off at 6.45 s(-1) in the scan rate range from 0.1 to 2.0 V s(-1). Oxidation and reduction of MP-11 by hydrogen peroxide and superoxide, respectively have been coupled to the direct electron transfer of MP-11.
KW  - Microperoxidase
KW  - Direct electron transfer
KW  - Nanoparticles
KW  - Hydrogen peroxide
KW  - Superoxide
KW  - Bioelectrocatalysis
Y1  - 2011
U6  - https://doi.org/10.1002/elan.201000535
SN  - 1040-0397
VL  - 23
IS  - 3
SP  - 611
EP  - 618
PB  - Wiley-Blackwell
CY  - Malden
ER  - 
TY  - JOUR
A1  - Scheller, Frieder W.
A1  - Wollenberger, Ursula
A1  - Lei, Chenghong
A1  - Jin, Wen
A1  - Ge, Bixia
A1  - Lehmann, Claudia
A1  - Lisdat, Fred
A1  - Fridman, Vadim
T1  - Bioelectrocatalysis by redox enzymes at modified electrodes
Y1  - 2002
UR  - www.elsevier.nl/inca/publications/6/0/1/3/4/7/index.htt
ER  - 
TY  - JOUR
A1  - Sigolaeva, L. V.
A1  - Markower, Alexander
A1  - Eremenko, A. V.
A1  - Makhaeva, G. F.
A1  - Malygin, V. V.
A1  - Kurochkin, I. N.
A1  - Scheller, Frieder W.
T1  - Bioelectrochemical anaysis of neuropathy targes esterase activity in blood
Y1  - 2001
ER  - 
TY  - JOUR
A1  - Warsinke, Axel
A1  - Benkert, Alexander
A1  - Scheller, Frieder W.
T1  - Biomolecular modules for creatinine determination
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Stancík, L.
A1  - Macholán, L.
A1  - Pluhacek, I.
A1  - Scheller, Frieder W.
T1  - Biosensing of rapeseed glucosinolates using amperometric enzyme electrodes based on membrane-bound glucose oxidase or tyrosinase
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Stancik, L.
A1  - Macholán, L.
A1  - Scheller, Frieder W.
T1  - Biosensing of tyrosinase inhibitors in nonaqueous solvents
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Eremenko, A. V.
A1  - Makower, Alexander
A1  - Jin, Wen
A1  - Rüger, P.
A1  - Scheller, Frieder W.
T1  - Biosensor based on an enzyme modified electrode for highly - sensitive measurement of polyphenols
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Wollenberger, Ursula
A1  - Hintsche, R.
A1  - Scheller, Frieder W.
T1  - Biosensors for analytical microsystems
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Warsinke, Axel
A1  - Stancik, L.
A1  - Macholán, L.
A1  - Pfeiffer, Dorothea
A1  - Scheller, Frieder W.
T1  - Biosensors for food analysis : application of biosensors to food requirements
Y1  - 1998
SN  - 0-85404-750-6
ER  - 
TY  - JOUR
A1  - Pfeiffer, Dorothea
A1  - Scheller, Frieder W.
A1  - McNeil, C. J.
A1  - Schulmeister, Thomas
T1  - Cascade-like exponential substrate amplification in enzyme sensors
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Markower, Alexander
A1  - Wollenberger, Ursula
A1  - Hörtnagel, H.
A1  - Pfeiffer, Dorothea
A1  - Scheller, Frieder W.
T1  - Catecholamine detection using enzymatic amplification
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Kleinjung, Frank
A1  - Ehrentreich-Förster, Eva
A1  - Scheller, Frieder W.
T1  - Changing functionality of surfaces by directed self-assembly using oligonucleotides - the oligo-tag
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Gajovic, Nenad
A1  - Warsinke, Axel
A1  - Huang, T.
A1  - Schulmeister, Thomas
A1  - Scheller, Frieder W.
T1  - Characterization and mathematical modelling of a novel bienzyme electrode for L-malate with cofactor recycling
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Stöcklein, Walter F. M.
A1  - Warsinke, Axel
A1  - Micheel, Burkhard
A1  - Höhne, Wolfgang
A1  - Woller, Jochen
A1  - Kempter, Gerhard
A1  - Scheller, Frieder W.
T1  - Characterization of a monoclonal antibody and its Fab fragment against diphenylurea hapten with BIA
Y1  - 1998
SN  - 3-8154-3540-4
ER  - 
TY  - JOUR
A1  - Halamek, Jan
A1  - Teller, Carsten
A1  - Zeravik, Jiri
A1  - Fournier, Didier
A1  - Makower, Alexander
A1  - Scheller, Frieder W.
T1  - Characterization of binding of cholinesterases to surface immobilized ligands
N2  - We summarize here the development of various piezoelectric biosensors utilizing cholinesterase (ChE) as the recognition element. In our work we studied the interaction between cholinesterase and its ligands (propidium, carnitine, benzylgonine-1,8-diamino-3,4-dioxaoctane (BZE-DADOO) and paraoxon). The sensor modification was based on a self-assembled monolayer (SAM) of a thiol compound (11-mercaptoundecanoic acid) on the gold electrode and the subsequent covalent coupling of the cholinesterase ligand to this SAM. The ligand-modified piezoelectric sensors were placed in a flow system to allow the on-line monitoring of cholinesterase binding and the enzymatic activity quantification by amperometry. Cholinesterases from different species-acetylcholinesterase (AChE) from Electrophorus electricus , AChE from Drosophila melanogaster , and butyrylcholinesterase (BChE) of human origin-were tested on the various immobilized ligands. Our research allowed the development of a competitive assay for the detection of organophosphates in river water samples using the BZE-DADOO-modified piezosensor. Another direction of research was pointed on the characterization of the interactions between ChE and its ligands. The kinetic binding constants were derived using a one- to-one binding model
Y1  - 2006
UR  - http://www.informaworld.com/openurl?genre=journal&issn=0003-2719
U6  - https://doi.org/10.1080/00032710600713107
SN  - 0003-2719
ER  - 
TY  - JOUR
A1  - Loew, Noya
A1  - Scheller, Frieder W.
A1  - Wollenberger, Ursula
T1  - Characterization of self-assembling of glucose dehydrogenase in mono- and multilayers on gold electrodes
N2  - Glucose dehydrogenase (GDH) was assembled electrostatically onto QCM-gold electrodes by their sequential deposition with anionic polyelectrolytes such as PSS and PASA. For the layer-by-layer arrangements both the microgravimetric and the electrochemical sensor signal were followed. Increasing amounts of GDH were deposited by stepwise formation of alternating layers of GDH and PSS or PASA. The mass increase was about 1.88 mug/cm(2) for one GDH/ PASA bilayer and 2.4 mug/cm(2) for a GDH/PSS bilayer. The addition of phenolic compounds resulted in an oxidation current, which could be catalytically increased by the GDH catalysed reaction in the presence of glucose. The system functions as glucose sensor when quinones are present in nonlimiting amount. The amperometric response was already diffusion limited when a single layer of GDH was adsorbed. The sensor sensitivity increased by a factor of 10 when MSA was used instead of MUA as initial electrode modifier
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Neumann, Bettina
A1  - Yarman, Aysu
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
T1  - Characterization of the enhanced peroxidatic activity of amyloid beta peptide-hemin complexes towards neurotransmitters
JF  - Analytical & bioanalytical chemistry
N2  - Binding of heme to the amyloid peptides A beta 40/42 is thought to be an initial step in the development of symptoms in the early stages of Alzheimer's disease by enhancing the intrinsic peroxidatic activity of heme. We found considerably higher acceleration of the reaction for the physiologically relevant neurotransmitters dopamine and serotonin than reported earlier for the artificial substrate 3,3',5,5'-tetramethylbenzidine (TMB). Thus, the binding of hemin to A beta peptides might play an even more crucial role in the early stages of Alzheimer's disease than deduced from these earlier results. To mimic complex formation, a new surface architecture has been developed: The interaction between the truncated amyloid peptide A beta 1-16 and hemin immobilized on an aminohexanethiol spacer on a gold electrode has been analyzed by cyclic voltammetry. The resulting complex has a redox pair with a 25 mV more cathodic formal potential than hemin alone.
KW  - Peroxidatic activity
Y1  - 2014
U6  - https://doi.org/10.1007/s00216-014-7822-8
SN  - 1618-2642
SN  - 1618-2650
VL  - 406
IS  - 14
SP  - 3359
EP  - 3364
PB  - Springer
CY  - Heidelberg
ER  - 
TY  - JOUR
A1  - Lei, Chenghong
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
T1  - Clay based direct electrochemistry of myoglobin
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Lei, Chenghong
A1  - Wollenberger, Ursula
A1  - Jung, Christiane
A1  - Scheller, Frieder W.
T1  - Clay-bridged electron transfer between cytochrome P450(cam) and electrode
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Scheller, Frieder W.
A1  - Pfeiffer, Dorothea
T1  - Commercial devices based on amperometric biosensors
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Beissenhirtz, Moritz Karl
A1  - Kwan, R. C. H.
A1  - Ko, K. M.
A1  - Renneberg, Reinhard
A1  - Scheller, Frieder W.
A1  - Lisdat, Fred
T1  - Comparing in vitro electrochemical measurement of superoxide scavenging activity with an in vivo assessment of antioxidant potential in Chinese tonifying herbs
N2  - The in vitro superoxide scavenging activity (as determined by electrochemical measurement) and the in vivo antioxidant potential (as determined by a mouse model of carbon tetrachloride (CCl4) hepatotoxicity) of methanolic extracts prepared from 10 Chinese tonifying herbs were compared. Electrochemical measurement using a cytochrome c (Cyt. c) sensor showed that all of the tested herbal extracts exhibited a medium superoxide scavenging activity of different potency, as indicated by their IC50 values. The in vivo measurement demonstrated that 80% of the herbal extracts displayed in vivo antioxidant potential, as assessed by the percentage of protection of the activity of plasma alanine aminotransferases and the hepatic glutathione regeneration capacity under CCl4-intoxicated condition. Although the in vitro antioxidant activity did not correlate quantitatively with the in vivo antioxidant potential, for 8 out of 10 samples a similar tendency was found. The rapid amperometric assessment of antioxidant potential by Cyt. c sensor may offer a convenient and direct method for screening as well as the quality control of herbal products. Copyright (C) 2004 John Wiley Sons, Ltd
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Gajovic, Nenad
A1  - Warsinke, Axel
A1  - Scheller, Frieder W.
T1  - Comparsion of two enzyme sequences for a novel L-malate biosensor
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Hock, Bertold
A1  - Scheller, Frieder W.
T1  - Conclusions and outlook
Y1  - 2001
ER  - 
TY  - JOUR
A1  - Riedel, M.
A1  - Sabir, N.
A1  - Scheller, Frieder W.
A1  - Parak, Wolfgang J.
A1  - Lisdat, Fred
T1  - Connecting quantum dots with enzymes
BT  - mediator-based approaches for the light-directed read-out of glucose and fructose oxidation
JF  - Nanoscale
N2  - The combination of the biocatalytic features of enzymes with the unique physical properties of nanoparticles in a biohybrid system provides a promising approach for the development of advanced bioelectrocatalytic devices. This study describes the construction of photoelectrochemical signal chains based on CdSe/ZnS quantum dot (QD) modified gold electrodes as light switchable elements, and low molecular weight redox molecules for the combination with different biocatalysts. Photoelectrochemical and photoluminescence experiments verify that electron transfer can be achieved between the redox molecules hexacyanoferrate and ferrocene, and the QDs under illumination. Since for both redox mediators a concentration dependent photocurrent change has been found, light switchable enzymatic signal chains are built up with fructose dehydrogenase (FDH) and pyrroloquinoline quinone-dependent glucose dehydrogenase ((PQQ) GDH) for the detection of sugars. After immobilization of the enzymes at the QD electrode the biocatalytic oxidation of the substrates can be followed by conversion of the redox mediator in solution and subsequent detection at the QD electrode. Furthermore, (PQQ) GDH has been assembled together with ferrocenecarboxylic acid on top of the QD electrode for the construction of a funtional biohybrid architecture, showing that electron transfer can be realized from the enzyme over the redox mediator to the QDs and subsequently to the electrode in a completely immobilized fashion. The results obtained here do not only provide the basis for light-switchable biosensing and bioelectrocatalytic applications, but may also open the way for self-driven point-of-care systems by combination with solar cell approaches (power generation at the QD electrode by enzymatic substrate consumption).
Y1  - 2017
U6  - https://doi.org/10.1039/c7nr00091j
SN  - 2040-3364
SN  - 2040-3372
VL  - 9
SP  - 2814
EP  - 2823
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  - 
TY  - JOUR
A1  - Jin, Wen
A1  - Wollenberger, Ursula
A1  - Bier, Frank Fabian
A1  - Scheller, Frieder W.
T1  - Construction and characterization of multi-layer-enzyme electrode : covalent binding of quinoprotein glucose dehydrogenase onto gold electrodes
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Pfeiffer, Dorothea
A1  - Yang, L.
A1  - Scheller, Frieder W.
A1  - Kissinger, P. T.
T1  - Continous measurement of lactate in microdialysate
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Yarman, Aysu
A1  - Scheller, Frieder W.
T1  - Coupling biocatalysis with molecular imprinting in a biomimetic sensor
JF  - Angewandte Chemie : a journal of the Gesellschaft Deutscher Chemiker ; International edition
KW  - biomimetic sensors
KW  - electropolymers
KW  - enzymes
KW  - hierarchical structures
KW  - molecularly imprinted polymers
Y1  - 2013
U6  - https://doi.org/10.1002/anie.201305368
SN  - 1433-7851
SN  - 1521-3773
VL  - 52
IS  - 44
SP  - 11521
EP  - 11525
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Scheller, Frieder W.
A1  - Bauer, Christian G.
A1  - Markower, Alexander
A1  - Wollenberger, Ursula
A1  - Warsinke, Axel
A1  - Bier, Frank Fabian
T1  - Coupling of immunoassays with enzymatic recycling electrodes
Y1  - 2001
ER  - 
TY  - JOUR
A1  - Lei, Chenghong
A1  - Lisdat, Fred
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
T1  - Cytochrome c : Clay-modified electrode
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Scheller, Frieder W.
A1  - Jin, Wen
A1  - Ehrentreich-Förster, Eva
A1  - Ge, Bixia
A1  - Lisdat, Fred
A1  - Büttemeyer, R.
A1  - Wollenberger, Ursula
T1  - Cytochrome c based superoxide sensor for in vivo application
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Bistolas, Nikitas
A1  - Wollenberger, Ursula
A1  - Jung, Christiane
A1  - Scheller, Frieder W.
T1  - Cytochrome P450 biosensors : a review
N2  - Cytochrome P450 (CYP) is a large family of enzymes containing heme as the active site. Since their discovery and the elucidation of their structure, they have attracted the interest of scientist for many years, particularly due to their catalytic abilities. Since the late 1970s attempts have concentrated on the construction and development of electrochemical sensors. Although sensors based on mediated electron transfer have also been constructed, the direct electron transfer approach has attracted most of the interest. This has enabled the investigation of the electrochemical properties of the various isoforms of CYP. Furthermore, CYP utilized to construct biosensors for the determination of substrates important in environmental monitoring, pharmaceutical industry and clinical practice. (c) 2004 Elsevier B. V. All rights reserved
Y1  - 2005
ER  - 
TY  - JOUR
A1  - Stöcklein, Walter F. M.
A1  - Warsinke, Axel
A1  - Micheel, Burkhard
A1  - Höhne, Wolfgang
A1  - Woller, Jochen
A1  - Kempter, Gerhard
A1  - Scheller, Frieder W.
T1  - Detection of diphenylurea derivatives with biospecific interaction analysis (BIA) : Kinetic investigations
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Ehrentreich-Förster, Eva
A1  - Scheller, Frieder W.
A1  - Bier, Frank Fabian
T1  - Detection of progesterone in whole blood samples
N2  - The progesterone concentration in blood samples can be utilised as a marker for the diagnosis of early pregnancy, endocrinopathy and virilism. Here, we describe a method for progesterone detection and measurement in whole blood samples by a surface sensitive biosensor used in conjunction with an integrated optical grating coupler. This device determines refractive index changes near the biosensor's surface. Hence, biological species bound to a surface layer can be measured in real-time without any label. For the measurements, we have modified the indirect competitive immonoassay principle. The concentration of the progesterone antibody was kept at 1 µg/ml. Progesterone concentration was determined in buffer solution and whole blood in a range between 0.005 and 10 ng/ml. The detection limit was determined to be 3 pM. The relative standard deviation was calculated to be 3.5%.
Y1  - 2003
ER  - 
TY  - JOUR
A1  - Pieper-Fürst, U.
A1  - Kleuser, U.
A1  - Stöcklein, Walter F. M.
A1  - Warsinke, Axel
A1  - Scheller, Frieder W.
T1  - Detection of subicomolar concentrations of human matrix metalloproteinase-2 by an optical biosensor
N2  - We describe in this paper the development of a one-step sandwich assay for the highly sensitive and fast detection of human matrix metalloproteinase (MMP)-2 (EC 3.4.24.24), using surface plasmon resonance (SPR). For the assay, two ligands were selected: monoclonal anti-MMP-2 antibody Ab-2 and the tissue inhibitor of metalloproteinases (TIMP)-2. They were chosen on the basis of (1) their affinities to MMP-2, (2) the efficiency of immobilization to the sensor chip, (3) the efficiency of adsorption to colloidal gold, and (4) the stability of these protein-coated gold particles. The assay included mixing of MMP-2 with antibody Ab-2 adsorbed to colloidal gold with a diameter of about 20 rim and injection into the flowcell of the SPR instrument containing immobilized TIMP-2. By using colloidal gold particles an amplification factor of 114 and a detection limit of 0.5 pM for MMP-2 were obtained. The precision of the assay was high even at low analyte concentrations, the standard deviation being 8.3% for five determinations of 1 pM MMP- 2. No significant binding was observed with the structurally related MMP-9. The assay is far more sensitive and faster than commonly used methods for MMP-2 detection. As TIMP-bound MMP-2 is not detected by this method, the assay can be applied for measuring free MMP-2, reflecting the imbalance of free and inhibitor-bound enzyme in various pathological situations. (C) 2004 Elsevier Inc. All rights reserved
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Ignatov, S.
A1  - Ge, Bixia
A1  - Scheller, Frieder W.
A1  - Lisdat, Fred
T1  - Detection of the antioxidant activity detection of flavonoids by using superoxide sensor
Y1  - 2001
SN  - 1-58603-164-3
ER  - 
TY  - JOUR
A1  - Ghindilis, A. L.
A1  - Makower, Alexander
A1  - Bauer, Christian G.
A1  - Bier, Frank Fabian
A1  - Scheller, Frieder W.
T1  - Determination of p-aminophenol and catecholamines at picomolar concentrations based on recycling enzyme amplification
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Vijgenboom, E.
A1  - Vijgenboom, E.
A1  - Teppner, A. W. J. W.
A1  - Makower, Alexander
A1  - Scheller, Frieder W.
A1  - Canters, Gerard W.
A1  - Wollenberger, Ursula
T1  - Determination of phenolic compounds using recombinant tyrosinanse from Streptomyces antibioticus
Y1  - 2001
ER  - 
TY  - JOUR
A1  - Wollenberger, Ursula
A1  - Neumann, B.
A1  - Scheller, Frieder W.
T1  - Development of a biomimetic alkane sensor f
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Halámek, Jan
A1  - Wollenberger, Ursula
A1  - Stöcklein, Walter F. M.
A1  - Scheller, Frieder W.
T1  - Development of a biosensor for glycated hemoglobin
N2  - The development of an electrochemical piezoelectric sensor for the detection of glycated hemoglobin is presented. The total hemoglobin (Hb) content is monitored with a mass-sensitive quartz crystal modified with surfactants, and the glycated fraction of the immobilized Hb is determined by subsequent voltarnmetric measurement of the coupled ferroceneboronic acid. Different modifications of the sensor were tested for their hemoglobin binding ability. Deoxycholate (DOCA) was found to be the most suitable among the examined modifiers. Piezoelectric quartz crystals with gold electrodes were modified with DOCA by covalent binding to a pre-formatted 4-aminothiophenol monolayer. The properties of the Hb binding to DOCA and the pH effect on this interaction were studied. In the proposed assay for glycated hemoglobin at first an Hb sample is incubated with ferroceneboronic acid (FcBA), which binds to the fructosyl residue of the glycated Hb. Then this preincubated Hb sample is allowed to interact with the DOCA-modified piezoelectric quartz crystal. The binding is monitored by quartz crystal nanobalance QCN). The amount of FcBA present on the sensor surface is determined by square wave voltammetry. The binding of FcBA results in well-defined peaks with an EO' of +200 mV versus Ag/AgC1 (1 M KC1). The peak height depends on the degree of glycated Hb in the sample ranging from 0% to 20% of total Hb. The regeneration of the sensing surface is achieved by pepsin digestion of the deposited Hb. Thus the sensor can be re-used more than 30 times.
Y1  - 2007
UR  - http://www.sciencedirect.com/science/journal/00134686
U6  - https://doi.org/10.1016/j.electacta.2007.03.059
SN  - 0013-4686
ER  - 
TY  - JOUR
A1  - Stöcklein, Walter F. M.
A1  - Warsinke, Axel
A1  - Micheel, Burkhard
A1  - Kempter, Gerhard
A1  - Höhne, Wolfgang
A1  - Scheller, Frieder W.
T1  - Diphenylurea hapten sensing with a monoclonal antibody and its Fab fragment : kinetic and thermodynamic investigations
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Wollenberger, Ursula
A1  - Drungiliene, A.
A1  - Stöcklein, Walter F. M.
A1  - Kulys, J.
A1  - Scheller, Frieder W.
T1  - Direct electrocatalytic determination of dissolved peroxidases
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Loew, Noya
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
A1  - Katterle, Martin
T1  - Direct electrochemistry and spectroelectrochemistry of osmium substituted horseradish peroxidase
N2  - In this contribution the substitution of the central protoporphyrin IX iron complex of horseradish peroxidase by the respective osmium porphyrin complex is described. The direct electrochemical reduction of the Os containing horseradish peroxidase (OsHRP) was achieved at ITO and modified glassy carbon electrodes and in combination with spectroscopy revealed the three redox couples (OsHRP)-H-III/(OsHRP)-H-IV, (OsHRP)-H-IV/(OsHRP)-H-V and (OsHRP)-H-V/ (OsHRP)-H-VI. The midpoint potentials differ dependent on the electrode material used with E-1/2 (Os-III/IV) of -0.4 V (ITO) and -0.25 V (GC), E-1/2 (Os-IV/V) of -0.16 V (ITO) and +0.10 V (GC), and E-1/2 (Os-V/VI)of +018 V (ITO), respectively Moreover, with immobilised OsHRP the direct electrocatalytic reduction of hydrogen peroxide and tert-butyl hydroperoxide was observed. In comparison to electrodes modified with native HRP the sensitivity of the OsHRP-electrode for tert-butyl hydroperoxide is higher.
Y1  - 2009
UR  - http://www.sciencedirect.com/science/journal/15675394
U6  - https://doi.org/10.1016/j.bioelechem.2009.03.015
SN  - 1567-5394
ER  - 
TY  - JOUR
A1  - Tanne, Johannes
A1  - Jeoung, Jae-Hun
A1  - Peng, Lei
A1  - Yarman, Aysu
A1  - Dietzel, Birgit
A1  - Schulz, Burkhard
A1  - Schad, Daniel
A1  - Dobbek, Holger
A1  - Wollenberger, Ursula
A1  - Bier, Frank Fabian
A1  - Scheller, Frieder W.
T1  - Direct Electron Transfer and Bioelectrocatalysis by a Hexameric, Heme Protein at Nanostructured Electrodes
JF  - Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis
N2  - A nanohybrid consisting of poly(3-aminobenzenesulfonic acid-co-aniline) and multiwalled carbon nanotubes [MWCNT-P(ABS-A)]) on a gold electrode was used to immobilize the hexameric tyrosine-coordinated heme protein (HTHP). The enzyme showed direct electron transfer between the heme group of the protein and the nanostructured surface. Desorption of the noncovalently bound heme from the protein could be excluded by control measurements with adsorbed hemin on aminohexanthiol-modified electrodes. The nanostructuring and the optimised charge characteristics resulted in a higher protein coverage as compared with MUA/MU modified electrodes. The adsorbed enzyme shows catalytic activity for the cathodic H2O2 reduction and oxidation of NADH.
KW  - HTHP
KW  - Nanohybrid
KW  - Poylaniline
KW  - Multiwalled carbon nanotube
Y1  - 2015
U6  - https://doi.org/10.1002/elan.201500231
SN  - 1040-0397
SN  - 1521-4109
VL  - 27
IS  - 10
SP  - 2262
EP  - 2267
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Jin, Wen
A1  - Bernhardt, Rita
A1  - Stöcklein, Walter F. M.
A1  - Scheller, Frieder W.
T1  - Direct electron transfer of adrenodoxin-a [2Fe-2S] protein-- and its mutants on modified gold electrode
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Wu, Yunhua
A1  - Wollenberger, Ursula
A1  - Hofrichter, Martin
A1  - Ullrich, Rene
A1  - Scheibner, Katrin
A1  - Scheller, Frieder W.
T1  - Direct electron transfer of Agrocybe aegerita peroxygenase at electrodes modified with chitosan-capped Au nanoparticles and its bioelectrocatalysis to aniline
JF  - Sensors and actuators : B, Chemical
N2  - Three different sizes of chitosan-capped Au nanoparticles were synthesized and were used to incorporate Agrocybe aegerita peroxygenase (AaeAPO) onto the surface of glassy carbon electrode. The direct electron transfer of AaeAPO was achieved in all films. The highest amount of electroactive enzyme and highest electron transfer rate constant k(s) of AaeAPO were obtained in the film with the smallest size of chitosan-capped Au nanoparticles.
 In anaerobic solutions, quasi-reversible oxidation and reduction are obtained with a formal potential of -0.280V vs. Ag/AgCl 1 M KCl in 100 mM (pH 7.0) PBS at scan rate of 1 V s(-1). Bioelectrocatalytic reduction currents can be obtained with the AaeAPO-modified electrode on addition of hydrogen peroxide. This reaction was suppressed when sodium azide, an inhibitor of AaeAPO, was present. Furthermore, the peroxide-dependent conversion of aniline was characterized and it was found that a polymer product via p-aminophenol is formed. And the AaeAPO biosensor was applied to determine aniline and p-aminophenol.
KW  - Agrocybe aegerita peroxygenase
KW  - Au nanoparticles
KW  - Direct electron transfer
KW  - Aniline biosensor
KW  - Bioelectrocatalysis
Y1  - 2011
U6  - https://doi.org/10.1016/j.snb.2011.09.090
SN  - 0925-4005
VL  - 160
IS  - 1
SP  - 1419
EP  - 1426
PB  - Elsevier
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Shumyantseva, V. V.
A1  - Ivanov, Y. D.
A1  - Bistolas, Nikitas
A1  - Scheller, Frieder W.
A1  - Archakov, Alexander I.
A1  - Wollenberger, Ursula
T1  - Direct electron transfer of cytochrome P450 2B4 at electrodes modified with non-ionic detergent and colloidal clay nanoparticles
N2  - A method for construction of biosensors with membranous cytochrome P450 isoenzymes was developed based on clay/ detergent/protein mixed films. Thin films of sodium montmorillonite colloid with incorporated cytochrome P450 2134 (CYP2B4) with nonionic detergent were prepared on glassy carbon electrodes. The modified electrodes were electrochemically characterized, and bio-electrocatalytic reactions were followed. CYP2B4 can be reduced fast on clay- modified glassy carbon electrodes in the presence of the nonionic detergent Tween 80. In anaerobic solutions, reversible oxidation and reduction is obtained with a formal potential between -0.292 and - 0.305 V vs Ag/AgCl 1 M KCl depending on the preparation of the biosensor. In air-saturated solution, bio-electrocatalytic reduction currents can be obtained with the CYP2B4-modified electrode on addition of typical substrates such as aminopyrine and benzphetamine. This reaction was suppressed when methyrapone, an inhibitor of P450 reactions, was present. Measurement of product formation also indicates the bioelectrocatialysis by CYP2B4
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Paeschke, Manfred
A1  - Hintsche, Rainer
A1  - Wollenberger, Ursula
A1  - Jin, Wen
A1  - Scheller, Frieder W.
T1  - Dynamic redox recycling of cytochrome c
Y1  - 1995
SN  - 0022-0728
ER  - 
TY  - JOUR
A1  - Stöcklein, Walter F. M.
A1  - Scheller, Frieder W.
A1  - Abuknesha, Rhamadan
T1  - Effects of organic solvents on semicontinuous immunochemical detection of coumarin derivatives
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Beissenhirtz, Moritz Karl
A1  - Scheller, Frieder W.
A1  - Stöcklein, Walter F. M.
A1  - Kurth, D.
A1  - Möhwald, Helmuth
A1  - Lisdat, Fred
T1  - Electroactive cytochrome c multilayers within a polyelectrolyte assembly
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Kulys, J.
A1  - Drungiliene, A.
A1  - Wollenberger, Ursula
A1  - Krikstopaitis, K.
A1  - Scheller, Frieder W.
T1  - Electroanalytical determination of peroxidases and laccases on carbon paste electrodes
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Spricigo, Roberto
A1  - Dronov, Roman
A1  - Lisdat, Fred
A1  - Leimkühler, Silke
A1  - Scheller, Frieder W.
A1  - Wollenberger, Ursula
T1  - Electrocatalytic sulfite biosensor with human sulfite oxidase co-immobilized with cytochrome c in a polyelectrolyte-containing multilayer
N2  - An efficient electrocatalytic biosensor for sulfite detection was developed by co-immobilizing sulfite oxidase and cytochrome c with polyaniline sulfonic acid in a layer-by-layer assembly. QCM, UV-Vis spectroscopy and cyclic voltammetry revealed increasing loading of electrochemically active protein with the formation of multilayers. The sensor operates reagentless at low working potential. A catalytic oxidation current was detected in the presence of sulfite at the modified gold electrode, polarized at +0.1 V ( vs. Ag/AgCl 1 M KCl). The stability of the biosensor performance was characterized and optimized. A 17-bilayer electrode has a linear range between 1 and 60 mu M sulfite with a sensitivity of 2.19 mA M-1 sulfite and a response time of 2 min. The electrode retained a stable response for 3 days with a serial reproducibility of 3.8% and lost 20% of sensitivity after 5 days of operation. It is possible to store the sensor in a dry state for more than 2 months. The multilayer electrode was used for determination of sulfite in unspiked and spiked samples of red and white wine. The recovery and the specificity of the signals were evaluated for each sample.
Y1  - 2009
UR  - http://www.springerlink.com/content/100417
U6  - https://doi.org/10.1007/s00216-008-2432-y
SN  - 1618-2642
ER  - 
TY  - JOUR
A1  - Kapp, Andreas
A1  - Beissenhirtz, Moritz Karl
A1  - Geyer, F.
A1  - Scheller, Frieder W.
A1  - Viezzoli, Maria Silvia
A1  - Lisdat, Fred
T1  - Electrochemical and sensorial behaviour of SOD mutants immobilized on gold electrodes in aqueous / organic solvent mixtures
Y1  - 2006
UR  - http://www3.interscience.wiley.com/cgi-bin/jhome/26571/
U6  - https://doi.org/10.1002/elan.200603620
SN  - 1040-0397
ER  - 
TY  - JOUR
A1  - Lisdat, Fred
A1  - Ge, Bixia
A1  - Stöcklein, Walter F. M.
A1  - Scheller, Frieder W.
A1  - Meyer, T.
T1  - Electrochemical behaviour and nitric oxides interaction of immobilised cytochrome c from Rhodocyclus gelatinosus
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Mak, Wing Cheung
A1  - Cheung, Kwan Yee
A1  - Trau, Dieter
A1  - Warsinke, Axel
A1  - Scheller, Frieder W.
A1  - Renneberg, Reinhard
T1  - Electrochemical bioassay utilizing encapsulated electrochemical active microcrystal biolabels
N2  - A new approach to perform electrochemical immunoassay based on the utilization of encapsulated microcrystal was developed. The microcrystal labels create a "supernova effect" upon exposure to a desired releasing agent. The microcrystal cores dissolve, and large amounts of signal-generating molecules diffuse across the capsule wall into the outer environment. Layer-by-Layer (LbL) technology was employed for the encapsulation of electrochemical signal- generating microcrystals (ferrocene microcrystals). The encapsulated microcrystals were conjugated with antibody molecules through the adsorption process. The biofunctionalized microcrystals were utilized as a probe for immunoassays. The microcrystal-based label system provided a high-signal molecule to antibody (SIP) ratio of 10(4)-10(5). Microcrystal biolabels with different antibody surface coverage (1.60-5.05 mg m(-2)) were subjected to a solid-phase immunoassay for the detection of mouse immunoglobulin G (M-IgG) molecules. The microcrystal-based immunoassay for the detection of M-IgG performed with microcrystals having antibody surface coverage of 5.05 mg m(-2) showed a sensitivity of 3.93 nA  g(- 1) L-1 with a detection limit of 2.82  g L-1
Y1  - 2005
SN  - 0003-2700
ER  - 
TY  - JOUR
A1  - Chen, Jian
A1  - Stöcklein, Walter F. M.
A1  - Scheller, Frieder W.
A1  - Wollenberger, Ursula
T1  - Electrochemical determination of human hemoglobin by using ferrocene carboxylic acid modified carbon powder microelectrode
Y1  - 2003
ER  - 
TY  - JOUR
A1  - Dechtrirat, Decha
A1  - Gajovic-Eichelmann, Nenad
A1  - Wojcik, Felix
A1  - Hartmann, Laura
A1  - Bier, Frank Fabian
A1  - Scheller, Frieder W.
T1  - Electrochemical displacement sensor based on ferrocene boronic acid tracer and immobilized glycan for saccharide binding proteins and E. coli
JF  - Biosensors and bioelectronics : the principal international journal devoted to research, design development and application of biosensors and bioelectronics
N2  - Pathogens such as viruses and bacteria use their envelope proteins and their adhesin lectins to recognize the glycan residues presented on the cell surface of the target tissues. This principle of recognition is used in a new electrochemical displacement sensor for the protein concanavalin A (ConA). A gold electrode was first modified with a self-assembled monolayer of a thiolated mannose/OEG conjugate and a ferrocene boroxol derivative was pre-assembled as reporter molecule onto the mannose surface. The novel tracer molecule based on a 2-hydroxymethyl phenyl boronic acid derivative binds even at neutral pH to the saccharides which could expand the application towards biological samples (i.e., urine and feces). Upon the binding of ConA, the tracer was displaced and washed away from the sensor surface leading to a decrease in the electrochemical signal. Using square wave voltammetry (SWV), the concentration of ConA in the sample solution could be determined in the dynamic concentration range established from 38 nmol L-1 to 5.76 mu mol L-1 with a reproducible detection limit of 1 mu g mL(-1) (38 nmol L-1) based on the signal-to-noise ratio (S/N=3) with fast response of 15 min. The new reporter molecule showed a reduced non-specific displacement by BSA and ribonuclease A. The sensor was also successfully transferred to the first proof of principle for the detection of Escherichia coli exhibiting a detection limit of approximately 6 x 102 cells/mL Specificity of the displacement by target protein ConA and E. coli was demonstrated since the control proteins (i.e., BSA and RNaseA) and the control E. coli strain, which lack of type 1 fimbriae, were ineffective. (C) 2014 Elsevier B.V. All rights reserved.
KW  - Ferrocene benzoboroxol biosensor
KW  - Concanavalin A
KW  - Displacement
KW  - Escherichia coli
KW  - Ferrocene boronic acid
KW  - Self-assembled monolayer
Y1  - 2014
U6  - https://doi.org/10.1016/j.bios.2014.02.028
SN  - 0956-5663
SN  - 1873-4235
VL  - 58
SP  - 1
EP  - 8
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Warsinke, Axel
A1  - Benkert, Alexander
A1  - Scheller, Frieder W.
T1  - Electrochemical immunoassays
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Fridman, Vadim
A1  - Wollenberger, Ursula
A1  - Bogdanovskaya, V. A.
A1  - Lisdat, Fred
A1  - Ruzgas, T.
A1  - Lindgren, A.
A1  - Gorton, Lo
A1  - Scheller, Frieder W.
T1  - Electrochemical investigation of cellobiose oxidation by cellobiose dehydrogenase in the presence of cytochrome c as mediator
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Jin, Wen
A1  - Wollenberger, Ursula
A1  - Kärgel, E.
A1  - Schunck, W.-H.
A1  - Scheller, Frieder W.
T1  - Electrochemical investigation of the intermolecular electron transfer between cytochrome c and NADPH-cytochrome P450-reductase
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Ozcelikay, Goksu
A1  - Kurbanoglu, Sevinc
A1  - Zhang, Xiaorong
A1  - Söz, Çağla Kosak
A1  - Wollenberger, Ulla
A1  - Ozkan, Sibel A.
A1  - Yarman, Aysu
A1  - Scheller, Frieder W.
T1  - Electrochemical MIP Sensor for Butyrylcholinesterase
JF  - Polymers
N2  - 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.
KW  - molecularly imprinted polymers
KW  - biomimetic sensors
KW  - butyrylcholinesterase
KW  - o-phenylenediamine
KW  - rivastigmine
Y1  - 2019
U6  - https://doi.org/10.3390/polym11121970
SN  - 2073-4360
VL  - 11
IS  - 12
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Kulys, J.
A1  - Krikstopaitis, K.
A1  - Scheller, Frieder W.
A1  - Wollenberger, Ursula
T1  - Electrochemical parameters of phenoxazine derivatives in solution and at monolayer-modified gold electrodes
N2  - 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
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Welzel, H.-P.
A1  - Kossmehl, G.
A1  - Engelmann, G.
A1  - Neumann, B.
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
T1  - Electrochemical polymerization of functionalized thiohene derivatives for immobilization of proteins
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Pfeiffer, Dorothea
A1  - Schubert, Frank
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
T1  - Electrochemical sensors : enzyme electrodes and field effect transistors
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Ju, Huangxian
A1  - Liu, Songqin
A1  - Ge, Bixia
A1  - Lisdat, Fred
A1  - Scheller, Frieder W.
T1  - Electrochemistry of cytochrome c immobilized on colloidal gold modified carbon paste electrodes and its electrocatalytic activity
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Katterle, Martin
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
T1  - Electrochemistry of hemoglobin at modified silver electrodes is not a redox-process of iron protoporhyrin IX
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Ge, Bixia
A1  - Scheller, Frieder W.
A1  - Lisdat, Fred
T1  - Electrochemistry of immobilized CuZnSOD and FeSOD and their interaction with superoxide radicals
N2  - 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 ñ 4 mV and -154 ñ 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.
Y1  - 2003
ER  - 
TY  - JOUR
A1  - Lei, Chenghong
A1  - Wollenberger, Ursula
A1  - Bistolas, Nikitas
A1  - Guiseppi-Eli, A.
A1  - Scheller, Frieder W.
T1  - Electron transfer of hemoglobin at electrodes modified with colloidal clay nanoparticles
Y1  - 2002
ER  -