TY  - JOUR
A1  - Kapp, A.
A1  - Beissenhirtz, Moritz Karl
A1  - Geyer, F.
A1  - Scheller, F.
A1  - Viezzoli, Maria Silvia
A1  - Lisdat, Fred
T1  - Electrochemical and sensorial behavior of SOD mutants immobilized on gold electrodes in aqueous/organic solvent mixtures
JF  - Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis
N2  - A cysteine mutant of a monomeric human Cu, Zn-SOD (Glycine 61, Serine 142) has been immobilized directly on gold electrodes using the thiol groups introduced. The electrochemical behavior of the surface confined protein was studied in mixtures of aqueous buffer and DMSO up to an organic solvent content of 60%. The formal potential was found to be rather independent of the DMSO content. However, half peak width increased and the redoxactive amount clearly decreased with raising DMSO content. In addition, the kinetics of the heterogeneous electron transfer became slower; but still a quasireversible electrochemical conversion of the mutant SOD was feasible. Thus, the electrodes were applied for sensorial superoxide detection. At a potential of +220 mV vs. Ag/AgCl advantage was taken of the partial oxidation reaction of the enzyme. A defined superoxide signal was obtained in solutions up to 40% DMSO. The sensitivity of the mutant electrodes decreased linearly with the organic solvent content in solution but was still higher compared to conventional cyt.c based sensors. At DMSO concentrations higher than 40% no sensor response was detected.
KW  - SOD
KW  - mutants
KW  - gold electrodes
KW  - DMSO
KW  - electrochemistry
Y1  - 2006
U6  - https://doi.org/10.1002/elan.200603620
SN  - 1040-0397
VL  - 18
SP  - 1909
EP  - 1915
PB  - Wiley
CY  - Weinheim
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  - Nitsche, Andreas
A1  - Kurth, Andreas
A1  - Dunkhorst, Anna
A1  - Pänke, Oliver
A1  - Sielaff, Hendrik
A1  - Junge, Wolfgang
A1  - Muth, Doreen
A1  - Scheller, Frieder W.
A1  - Stöcklein, Walter F. M.
A1  - Pauli, Georg
A1  - Kage, Andreas
T1  - One-step selection of vaccinia virus binding DNA-aptamers by MonoLEX
Y1  - 2007
UR  - http://www.biomedcentral.com/1472-6750/7
U6  - https://doi.org/10.1186/1472-6750-7-48
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  - 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  - 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  - Kleuser, U.
A1  - Stöcklein, Walter F. M.
A1  - Pieper-Fürst, U.
A1  - Scheller, Frieder W.
T1  - Partikelverstärkte Oberflächenplasmonresonanz für die Quantifizierung von Matrix Metalloproteinase-2
Y1  - 2004
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  - 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  - Nießner, Reinhard
A1  - Broekaert, J.
A1  - Einax, J. W.
A1  - Scheller, Frieder W.
A1  - Stöcklein, Walter F. M.
T1  - Trendbericht analytische Biochemie 2000/2001
Y1  - 2002
ER  - 
TY  - JOUR
A1  - Stöcklein, Walter F. M.
A1  - Warsinke, Axel
A1  - Scheller, Frieder W.
T1  - Organic solvent modified enzyme-liked immunoassay for the detection of triazine herbicides
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Stöcklein, Walter F. M.
A1  - Scheller, Frieder W.
T1  - Enzymes and antibodies in organic media : analytical applications
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Kleinjung, Frank
A1  - Beier, Frank F.
A1  - Warsinke, Axel
A1  - Scheller, Frieder W.
T1  - Fibre-optic genosensor for specific determination of femtomolar DNA oligomers
Y1  - 1997
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  - 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  - Stöcklein, Walter F. M.
A1  - Scheller, Frieder W.
T1  - Einsatz von Enzymen und Antikörpern in organischen Lösungsmitteln
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Freaney, R.
A1  - MacShane, A.
A1  - Keaveny, T. V.
A1  - MacKenna, M.
A1  - Rabenstein, K.
A1  - Scheller, Frieder W.
A1  - Pfeiffer, Dorothea
A1  - Urban, G.
A1  - Moser, I.
A1  - Jobst, G.
A1  - Manz, A.
A1  - Verpoorte, E.
A1  - Widmer, M. W.
A1  - Diamond, D.
A1  - Dempsey, E.
A1  - deViteri, F. J. S.
A1  - Smyth, M.
T1  - Novel instrumentation for real-time monitoring using miniaturized flow systems with integrated biosensors
Y1  - 1997
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  - 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  - 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  - Stöcklein, Walter F. M.
A1  - Scheller, Frieder W.
T1  - Laccase : a marker enzyme for solvent modified immunoassays
Y1  - 1996
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  - Halámek, Jan
A1  - Wollenberger, Ursula
A1  - Stöcklein, Walter F. M.
A1  - Warsinke, Axel
A1  - Scheller, Frieder W.
T1  - Signal amplification in immunoassays using labeling via boronic acid binding to the sugar moiety of immunoglobulin G : proof of concept for glycated hemoglobin
N2  - A novel electrochemical immunoassay based on the multiple affinity labeling of the indicator antibody with an electro-active tag is presented. The concept is illustrated for the determination of the glycated hemoglobin HbA1c in hemoglobin samples. Hemoglobin is adsorbed to the surfactant-modified surface of a piezoelectric quartz crystal. Whereas the quartz crystal nanobalance is used to validate the total Hb binding, the HbA1c on the sensor surface is recognized by an antibody and quantified electrochemically after the sugar moieties of the antibody have been labeled in-situ with ferroceneboronic acid. The sensitivity of this sensor is about threefold higher than the sensitivity of a hemoglobin sensor, where the ferroceneboronic acid is bound directly to HbA1c.
Y1  - 2007
UR  - http://www.informaworld.com/openurl?genre=journal&issn=0003-2719
U6  - https://doi.org/10.1080/00032710701327096
SN  - 0003-2719
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  - Jin, Wen
A1  - Bernhardt, Rita
A1  - Lehmann, Claudia
A1  - Stöcklein, Walter F. M.
A1  - Brigelius-Flohé, Regina
A1  - Scheller, Frieder W.
T1  - Funktionalisierung von Elektroden für den direkten heterogenen Elektrotransfer
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Stöllner, Daniela
A1  - Stöcklein, Walter F. M.
A1  - Scheller, Frieder W.
A1  - Warsinke, Axel
T1  - Membrane-immobilized haptoglobin as affinity matrix for a hemoglobin-A1c-immunosensor
Y1  - 2002
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  - Stöcklein, Walter F. M.
A1  - Behrsing, Olaf
A1  - Scharte, Gudrun
A1  - Micheel, Burkhard
A1  - Benkert, Alexander
A1  - Schössler, W.
A1  - Warsinke, Axel
A1  - Scheller, Frieder W.
T1  - Enzyme kinetic assays with surface plasmon resonance (BIAcore) based on competition between enzyme and creatinine antibody
Y1  - 2000
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  - Stöcklein, Walter F. M.
A1  - Rohde, M.
A1  - Scharte, Gudrun
A1  - Behrsing, Olaf
A1  - Warsinke, Axel
A1  - Micheel, Burkhard
A1  - Scheller, Frieder W.
T1  - Sensitive detection of triazine and phenylurea pesticides in pure organic solvent by enzyme linked immunsorbent assay (ELISA): stabilities, solubilities and sensitives
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Stöcklein, Walter F. M.
A1  - Makower, Alexander
A1  - Bier, Frank Fabian
A1  - Scheller, Frieder W.
T1  - Enzyme sensors and enzyme amplifification systems
Y1  - 1997
ER  -