TY  - GEN
A1  - Scheller, Frieder W.
A1  - Sakar Dasdan, Dolunay
T1  - Selected papers presented on the 2nd International Conference on the New Trends in Chemistry, Zagreb, Croatia, April 19-22, 2016 Preface
T2  - Bulgarian chemical communications : journal of the Chemical Institutes of the Bulgarian Academy of Sciences and of the Bulgarian Chemical Society = Izvestija po chimija
Y1  - 2016
SN  - 0324-1130
VL  - 48
SP  - 4
EP  - 4
PB  - Bulgarian Academy of Sciences
CY  - Sofia
ER  - 
TY  - JOUR
A1  - Peng, Lei
A1  - Yarman, Aysu
A1  - Jetzschmann, Katharina J.
A1  - Jeoung, Jae-Hun
A1  - Schad, Daniel
A1  - Dobbek, Holger
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
T1  - Molecularly Imprinted Electropolymer for a Hexameric Heme Protein with Direct Electron Transfer and Peroxide Electrocatalysis
JF  - SENSORS
N2  - For the first time a molecularly imprinted polymer (MIP) with direct electron transfer (DET) and bioelectrocatalytic activity of the target protein is presented. Thin films of MIPs for the recognition of a hexameric tyrosine-coordinated heme protein (HTHP) have been prepared by electropolymerization of scopoletin after oriented assembly of HTHP on a self-assembled monolayer (SAM) of mercaptoundecanoic acid (MUA) on gold electrodes. Cavities which should resemble the shape and size of HTHP were formed by template removal. Rebinding of the target protein sums up the recognition by non-covalent interactions between the protein and the MIP with the electrostatic attraction of the protein by the SAM. HTHP bound to the MIP exhibits quasi-reversible DET which is reflected by a pair of well pronounced redox peaks in the cyclic voltammograms (CVs) with a formal potential of -184.4 +/- 13.7 mV vs. Ag/AgCl (1 M KCl) at pH 8.0 and it was able to catalyze the cathodic reduction of peroxide. At saturation the MIP films show a 12-fold higher electroactive surface concentration of HTHP than the non-imprinted polymer (NIP).
KW  - hydrogen peroxide
KW  - bioelectrocatalysis
KW  - molecularly imprinted polymers
KW  - direct electron transfer
KW  - self-assembled monolayer
Y1  - 2016
U6  - https://doi.org/10.3390/s16030272
SN  - 1424-8220
VL  - 16
SP  - 1343
EP  - 1364
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Erdossy, Julia
A1  - Horvath, Viola
A1  - Yarman, Aysu
A1  - Scheller, Frieder W.
A1  - Gyurcsanyi, Robert E.
T1  - Electrosynthesized molecularly imprinted polymers for protein recognition
JF  - Trends in Analytical Chemistry
N2  - Molecularly imprinted polymers (MIPs) for the recognition of proteins are expected to possess high affinity through the establishment of multiple interactions between the polymer matrix and the large number of functional groups of the target. However, while highly affine recognition sites need building blocks rich in complementary functionalities to their target, such units are likely to generate high levels of nonspecific binding. This paradox, that nature solved by evolution for biological receptors, needs to be addressed by the implementation of new concepts in molecular imprinting of proteins. Additionally, the structural variability, large size and incompatibility with a range of monomers made the development of protein MIPs to take a slow start. While the majority of MIP preparation methods are variants of chemical polymerization, the polymerization of electroactive functional monomers emerged as a particularly advantageous approach for chemical sensing application. Electropolymerization can be performed from aqueous solutions to preserve the natural conformation of the protein templates, with high spatial resolution and electrochemical control of the polymerization process. This review compiles the latest results, identifying major trends and providing an outlook on the perspectives of electrosynthesised protein-imprinted MIPs for chemical sensing. (C) 2016 Elsevier B.V. All rights reserved.
KW  - Molecularly imprinted polymers
KW  - Proteins
KW  - Surface imprinting
KW  - Electropolymerization
KW  - Nanostructuring
KW  - Hybrid nanofilms
Y1  - 2016
U6  - https://doi.org/10.1016/j.trac.2015.12.018
SN  - 0165-9936
SN  - 1879-3142
VL  - 79
SP  - 179
EP  - 190
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Menger, Marcus
A1  - Yarman, Aysu
A1  - Erdössy, Júlia
A1  - Yildiz, Huseyin Bekir
A1  - Gyurcsányi, Róbert E.
A1  - Scheller, Frieder W.
T1  - MIPs and Aptamers for Recognition of Proteins in Biomimetic Sensing
JF  - Biosensors : open access journal
N2  - Biomimetic binders and catalysts have been generated in order to substitute the biological pendants in separation techniques and bioanalysis. The two major approaches use either "evolution in the test tube" of nucleotides for the preparation of aptamers or total chemical synthesis for molecularly imprinted polymers (MIPs). The reproducible production of aptamers is a clear advantage, whilst the preparation of MIPs typically leads to a population of polymers with different binding sites. The realization of binding sites in the total bulk of the MIPs results in a higher binding capacity, however, on the expense of the accessibility and exchange rate. Furthermore, the readout of the bound analyte is easier for aptamers since the integration of signal generating labels is well established. On the other hand, the overall negative charge of the nucleotides makes aptamers prone to non-specific adsorption of positively charged constituents of the sample and the "biological" degradation of non-modified aptamers and ionic strength-dependent changes of conformation may be challenging in some application.
KW  - biomimetic recognition elements
KW  - aptamers
KW  - molecularly imprinted polymers
KW  - chemical sensors
KW  - aptasensors
KW  - in vitro selection
KW  - SELEX
Y1  - 2016
U6  - https://doi.org/10.3390/bios6030035
SN  - 2079-6374
VL  - 6
SP  - 4399
EP  - 4413
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Yarman, Aysu
A1  - Scheller, Frieder W.
T1  - MIP-esterase/Tyrosinase Combinations for Paracetamol and Phenacetin
JF  - Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis
N2  - A new electrochemical MIP sensor for the most frequently used drug paracetamol (PAR) was prepared by electropolymerization of mixtures containing the template molecule and the functional monomers ophenylenediamine, resorcinol and aniline. The imprinting factor of 12 reflects the effective target binding to the MIP as compared with the non-imprinted electropolymer. Combination of the MIP with a nonspecific esterase allows the measurement of phenacetin - another analgesic drug. In the second approach the PAR containing sample solution was pretreated with tyrosinase in order to prevent electrochemical interferences by ascorbic acid and uric acid. Interference-free indication at a very low electrode potential without fouling of the electrode surface was achieved with the o-phenylenediamine: resorcinol-based MIP.
KW  - Paracetamol
KW  - Molecularly imprinted polymers
KW  - Electropolymerization
KW  - Tyrosinase
KW  - Esterase
KW  - Phenacetin
Y1  - 2016
U6  - https://doi.org/10.1002/elan.201600042
SN  - 1040-0397
SN  - 1521-4109
VL  - 28
SP  - 2222
EP  - 2227
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - GEN
A1  - Peng, Lei
A1  - Yarman, Aysu
A1  - Jetzschmann, Katharina J.
A1  - Jeoung, Jae-Hun
A1  - Schad, Daniel
A1  - Dobbek, Holger
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
T1  - Molecularly imprinted electropolymer for a hexameric heme protein with direct electron transfer and peroxide electrocatalysis
N2  - For the first time a molecularly imprinted polymer (MIP) with direct electron transfer (DET) and bioelectrocatalytic activity of the target protein is presented. Thin films of MIPs for the recognition of a hexameric tyrosine-coordinated heme protein (HTHP) have been prepared by electropolymerization of scopoletin after oriented assembly of HTHP on a self-assembled monolayer (SAM) of mercaptoundecanoic acid (MUA) on gold electrodes. Cavities which should resemble the shape and size of HTHP were formed by template removal. Rebinding of the target protein sums up the recognition by non-covalent interactions between the protein and the MIP with the electrostatic attraction of the protein by the SAM. HTHP bound to the MIP exhibits quasi-reversible DET which is reflected by a pair of well pronounced redox peaks in the cyclic voltammograms (CVs) with a formal potential of −184.4 ± 13.7 mV vs. Ag/AgCl (1 M KCl) at pH 8.0 and it was able to catalyze the cathodic reduction of peroxide. At saturation the MIP films show a 12-fold higher electroactive surface concentration of HTHP than the non-imprinted polymer (NIP).
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 362 
KW  - molecularly imprinted polymers
KW  - self-assembled monolayer
KW  - direct electron transfer
KW  - hydrogen peroxide
KW  - bioelectrocatalysis
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-400627
ER  - 
TY  - GEN
A1  - Menger, Marcus
A1  - Yarman, Aysu
A1  - Erdőssy, Júlia
A1  - Yildiz, Huseyin Bekir
A1  - Gyurcsányi, Róbert E.
A1  - Scheller, Frieder W.
T1  - MIPs and aptamers for recognition of proteins in biomimetic sensing
N2  - Biomimetic binders and catalysts have been generated in order to substitute the biological pendants in separation techniques and bioanalysis. The two major approaches use either "evolution in the test tube" of nucleotides for the preparation of aptamers or total chemical synthesis for molecularly imprinted polymers (MIPs). The reproducible production of aptamers is a clear advantage, whilst the preparation of MIPs typically leads to a population of polymers with different binding sites. The realization of binding sites in the total bulk of the MIPs results in a higher binding capacity, however, on the expense of the accessibility and exchange rate. Furthermore, the readout of the bound analyte is easier for aptamers since the integration of signal generating labels is well established. On the other hand, the overall negative charge of the nucleotides makes aptamers prone to non-specific adsorption of positively charged constituents of the sample and the "biological" degradation of non-modified aptamers and ionic strength-dependent changes of conformation may be challenging in some application.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 357 
KW  - biomimetic recognition elements
KW  - aptamers
KW  - molecularly imprinted polymers
KW  - chemical sensors
KW  - aptasensors
KW  - in vitro selection
KW  - SELEX
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-400496
ER  - 
TY  - JOUR
A1  - Yarman, Aysu
A1  - Dechtrirat, Decha
A1  - Bosserdt, Maria
A1  - Jetzschmann, Katharina J.
A1  - Gajovic-Eichelmann, Nenad
A1  - Scheller, Frieder W.
T1  - Cytochrome c-derived hybrid systems based on moleculary imprinted polymers
JF  - Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis
N2  - Hybrid architectures which combine a MIP with an immobilized affinity ligand or a biocatalyst sum up the advantages of both components. In this paper, hybrid architectures combining a layer of a molecularly imprinted electropolymer with a mini-enzyme or a self-assembled monolayer will be presented. (i) Microperoxidase-11 (MP-11) catalyzed oxidation of the drug aminopyrine on a product-imprinted sublayer: The peroxide dependent conversion of the analyte aminopyrine takes place in the MP-11 containing layer on top of a product-imprinted electropolymer on the indicator electrode. The hierarchical architecture resulted in the elimination of interfering signals for ascorbic acid and uric acid. An advantage of the new hierarchical structure is the separation of MIP formation by electropolymerization and immobilization of the catalyst. In this way it was for the first time possible to integrate an enzyme with a MIP layer in a sensor configuration. This combination has the potential to be transferred to other enzymes, e.g. P450, opening the way to clinically important analytes. (ii) Epitope-imprinted poly-scopoletin layer for binding of the C-terminal peptide and cytochrome c (Cyt c): The MIP binds both the target peptide and the parent protein almost eight times stronger than the non-imprinted polymer with affinities in the lower micromolar range. Exchange of only one amino acid in the peptide decreases the binding by a factor of five. (iii) MUA-poly-scopoletin MIP for cytochrome c: Cyt c bound to the MIP covered gold electrode exhibits direct electron transfer with a redox potential and rate constant typical for the native protein. The MIP cover layer suppresses the displacement of the target protein by BSA or myoglobin. The combination of protein imprinted polymers with an efficient electron transfer is a new concept for characterizing electroactive proteins such as Cyt c. The competition with other proteins shows that the MIP binds its target Cyt c preferentially and that molecular shape and the charge of protein determine the binding of interfering proteins.
KW  - Molecularly imprinted polymers
KW  - Microperoxidase-11
KW  - Cytochrome c
KW  - Catalytically active MIPs
KW  - Epitope imprinting
KW  - Monoclonal MIPs
Y1  - 2015
U6  - https://doi.org/10.1002/elan.201400592
SN  - 1040-0397
SN  - 1521-4109
VL  - 27
IS  - 3
SP  - 573
EP  - 586
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Peng, Lei
A1  - Utesch, Tillmann
A1  - Yarman, Aysu
A1  - Jeoung, Jae-Hun
A1  - Steinborn, Silke
A1  - Dobbek, Holger
A1  - Mroginski, Maria Andrea
A1  - Tanne, Johannes
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
T1  - Surface-Tuned Electron Transfer and Electrocatalysis of Hexameric Tyrosine-Coordinated Heme Protein
JF  - Chemistry - a European journal
N2  - Molecular modeling, electrochemical methods, and quartz crystal microbalance were used to characterize immobilized hexameric tyrosine-coordinated heme protein (HTHP) on bare carbon or on gold electrodes modified with positively and negatively charged self-assembled monolayers (SAMs), respectively. HTHP binds to the positively charged surface but no direct electron transfer (DET) is found due to the long distance of the active sites from the electrode surfaces. At carboxyl-terminated surfaces, the neutrally charged bottom of HTHP can bind to the SAM. For this "disc" orientation all six hemes are close to the electrode and their direct electron transfer should be efficient. HTHP on all negatively charged SAMs showed a quasi-reversible redox behavior with rate constant k(s) values between 0.93 and 2.86 s(-1) and apparent formal potentials E-app(0)' between -131.1 and -249.1 mV. On the MUA/MU-modified electrode, the maximum surface concentration corresponds to a complete monolayer of the hexameric HTHP in the disc orientation. HTHP electrostatically immobilized on negatively charged SAMs shows electrocatalysis of peroxide reduction and enzymatic oxidation of NADH.
KW  - electrochemistry
KW  - electron transfer
KW  - heme proteins
KW  - molecular modeling
KW  - monolayers
Y1  - 2015
U6  - https://doi.org/10.1002/chem.201405932
SN  - 0947-6539
SN  - 1521-3765
VL  - 21
IS  - 20
SP  - 7596
EP  - 7602
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Spricigo, Roberto
A1  - Leimkühler, Silke
A1  - Gorton, Lo
A1  - Scheller, Frieder W.
A1  - Wollenberger, Ursula
T1  - The Electrically Wired Molybdenum Domain of Human Sulfite Oxidase is Bioelectrocatalytically Active
JF  - European journal of inorganic chemistry : a journal of ChemPubSoc Europe
N2  - We report electron transfer between the catalytic molybdenum cofactor (Moco) domain of human sulfite oxidase (hSO) and electrodes through a poly(vinylpyridine)-bound [osmium(N,N'-methyl-2,2'-biimidazole)(3)](2+/3+) complex as the electron-transfer mediator. The biocatalyst was immobilized in this low-potential redox polymer on a carbon electrode. Upon the addition of sulfite to the immobilized separate Moco domain, the generation of a significant catalytic current demonstrated that the catalytic center is effectively wired and active. The bioelectrocatalytic current of the wired separate catalytic domain reached 25% of the signal of the wired full molybdoheme enzyme hSO, in which the heme b(5) is involved in the electron-transfer pathway. This is the first report on a catalytically active wired molybdenum cofactor domain. The formal potential of this electrochemical mediator is between the potentials of the two cofactors of hSO, and as hSO can occupy several conformations in the polymer matrix, it is imaginable that electron transfer from the catalytic site to the electrode through the osmium center occurs for the hSO molecules in which the Moco domain is sufficiently accessible. The observation of catalytic oxidation currents at low potentials is favorable for applications in bioelectronic devices.
KW  - Metalloenzymes
KW  - Enzyme catalysis
KW  - Immobilization
KW  - Osmium
Y1  - 2015
U6  - https://doi.org/10.1002/ejic.201500034
SN  - 1434-1948
SN  - 1099-0682
IS  - 21
SP  - 3526
EP  - 3531
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Jetzschmann, Katharina J.
A1  - Jagerszki, Gyula
A1  - Dechtrirat, Decha
A1  - Yarman, Aysu
A1  - Gajovic-Eichelmann, Nenad
A1  - Gilsing, Hans-Detlev
A1  - Schulz, Burkhard
A1  - Gyurcsanyi, Robert E.
A1  - Scheller, Frieder W.
T1  - Vectorially Imprinted Hybrid Nanofilm for Acetylcholinesterase Recognition
JF  - Advanced functional materials
N2  - Effective recognition of enzymatically active tetrameric acetylcholinesterase (AChE) is accomplished by a hybrid nanofilm composed of a propidium-terminated self-assembled monolayer (Prop-SAM) which binds AChE via its peripheral anionic site (PAS) and an ultrathin electrosynthesized molecularly imprinted polymer (MIP) cover layer of a novel carboxylate-modified derivative of 3,4-propylenedioxythiophene. The rebinding of the AChE to the MIP/Prop-SAM nanofilm covered electrode is detected by measuring in situ the enzymatic activity. The oxidative current of the released thiocholine is dependent on the AChE concentration from approximate to 0.04 x 10(-6) to 0.4 x 10(-6)m. An imprinting factor of 9.9 is obtained for the hybrid MIP, which is among the best values reported for protein imprinting. The dissociation constant characterizing the strength of the MIP-AChE binding is 4.2 x 10(-7)m indicating the dominant role of the PAS-Prop-SAM interaction, while the benefit of the MIP nanofilm covering the Prop-SAM layer is the effective suppression of the cross-reactivity toward competing proteins as compared with the Prop-SAM. The threefold selectivity gain provided by i) the shape-specific MIP filter, ii) the propidium-SAM, iii) signal generation only by the AChE bound to the nanofilm shows promise for assessing AChE activity levels in cerebrospinal fluid.
KW  - acetylcholinesterase
KW  - biomimetic sensors
KW  - molecularly imprinted electropolymers
KW  - peripheral anionic site
KW  - propidium
Y1  - 2015
U6  - https://doi.org/10.1002/adfm.201501900
SN  - 1616-301X
SN  - 1616-3028
VL  - 25
IS  - 32
SP  - 5178
EP  - 5183
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - 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  - Scheller, Frieder W.
A1  - Yarman, Aysu
A1  - Bachmann, Till
A1  - Hirsch, Thomas
A1  - Kubick, Stefan
A1  - Renneberg, Reinhard
A1  - Schumacher, Soeren
A1  - Wollenberger, Ursula
A1  - Teller, Carsten
A1  - Bier, Frank Fabian
ED  - Gu, MB
ED  - Kim, HS
T1  - Future of biosensors: a personal view
JF  - Advances in biochemical engineering, biotechnology
JF  - Advances in Biochemical Engineering-Biotechnology
N2  - 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.
KW  - Biosensors
KW  - Molecularly imprinted polymers
KW  - Personalized medicine
Y1  - 2014
SN  - 978-3-642-54143-8; 978-3-642-54142-1
U6  - https://doi.org/10.1007/10_2013_251
SN  - 0724-6145
VL  - 140
SP  - 1
EP  - 28
PB  - Springer
CY  - Berlin
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  - Yarman, Aysu
A1  - Scheller, Frieder W.
T1  - The first electrochemical MIP sensor for tamoxifen
JF  - Sensors
N2  - We present an electrochemical MIP sensor for tamoxifen (TAM)-a nonsteroidal anti-estrogen-which is based on the electropolymerisation of an O-phenylenediamine. resorcinol mixture directly on the electrode surface in the presence of the template molecule. Up to now only. bulk. MIPs for TAM have been described in literature, which are applied for separation in chromatography columns. Electro-polymerisation of the monomers in the presence of TAM generated a film which completely suppressed the reduction of ferricyanide. Removal of the template gave a markedly increased ferricyanide signal, which was again suppressed after rebinding as expected for filling of the cavities by target binding. The decrease of the ferricyanide peak of the MIP electrode depended linearly on the TAM concentration between 1 and 100 nM. The TAM-imprinted electrode showed a 2.3 times higher recognition of the template molecule itself as compared to its metabolite 4-hydroxytamoxifen and no cross-reactivity with the anticancer drug doxorubucin was found. Measurements at + 1.1 V caused a fouling of the electrode surface, whilst pretreatment of TAM with peroxide in presence of HRP generated an oxidation product which was reducible at 0 mV, thus circumventing the polymer formation and electrochemical interferences.
KW  - molecularly imprinted polymers
KW  - anticancer drug
KW  - tamoxifen
KW  - electropolymerisation
Y1  - 2014
U6  - https://doi.org/10.3390/s140507647
SN  - 1424-8220
VL  - 14
IS  - 5
SP  - 7647
EP  - 7654
PB  - MDPI
CY  - Basel
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  - Yarman, Aysu
A1  - Schulz, Christopher
A1  - Sygmund, Cristoph
A1  - Ludwig, Roland
A1  - Gorton, Lo
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
T1  - Third generation ATP sensor with enzymatic analyte recycling
JF  - Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis
N2  - For the first time the direct electron transfer of an enzyme - cellobiose dehydrogenase, CDH - has been coupled with the hexokinase catalyzed competition for glucose in a sensor for ATP. To enhance the signal output for ATP, pyruvate kinase was coimmobilized to recycle ADP by the phosphoenolpyruvate driven reaction. The new sensor overcomes the limit of 1:1 stoichiometry of the sequential or competitive conversion of ATP by effective enzymatic recycling of the analyte. The anodic oxidation of the glucose converting CDH proceeds at electrode potentials below 0 mV vs. Ag vertical bar AgCl thus potentially interfering substances like ascorbic acid or catecholamines do not influence the measuring signal. The combination of direct electron transfer of CDH with the enzymatic recycling results in an interference-free and oxygen-independent measurement of ATP in the lower mu molar concentration range with a lower limit of detection of 63.3 nM (S/N=3).
KW  - ATP
KW  - Third generation sensor
KW  - Enzymatic recycling
KW  - Cellobiose dehydrogenase
KW  - Hexokinase
KW  - Pyruvate kinase
Y1  - 2014
U6  - https://doi.org/10.1002/elan.201400231
SN  - 1040-0397
SN  - 1521-4109
VL  - 26
IS  - 9
SP  - 2043
EP  - 2048
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Yarman, Aysu
A1  - Badalyan, Artavazd
A1  - Gajovic-Eichelmann, Nenad
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
T1  - Enzyme electrode for aromatic compounds exploiting the catalytic activities of microperoxidase-11
JF  - Biosensors and bioelectronics : the principal international journal devoted to research, design development and application of biosensors and bioelectronics
N2  - 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.
KW  - Microperoxidase-11
KW  - Nanoparticles
KW  - p-Aminophenol
KW  - Aniline
KW  - Catechol
KW  - 4-Fluoroaniline
KW  - Biosensors
Y1  - 2011
U6  - https://doi.org/10.1016/j.bios.2011.09.004
SN  - 0956-5663
VL  - 30
IS  - 1
SP  - 320
EP  - 323
PB  - Elsevier
CY  - Oxford
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  - Yarman, Aysu
A1  - Gröbe, Glenn
A1  - Neumann, Bettina
A1  - Kinne, Mathias
A1  - Gajovic-Eichelmann, Nenad
A1  - Wollenberger, Ursula
A1  - Hofrichter, Martin
A1  - Ullrich, Rene
A1  - Scheibner, Katrin
A1  - Scheller, Frieder W.
T1  - The aromatic peroxygenase from Marasmius rutola-a new enzyme for biosensor applications
JF  - Analytical & bioanalytical chemistry
N2  - The aromatic peroxygenase (APO; EC 1.11.2.1) from the agraric basidomycete Marasmius rotula (MroAPO) immobilized at the chitosan-capped gold-nanoparticle-modified glassy carbon electrode displayed a pair of redox peaks with a midpoint potential of -278.5 mV vs. AgCl/AgCl (1 M KCl) for the Fe(2+)/Fe(3+) redox couple of the heme-thiolate-containing protein. MroAPO oxidizes aromatic substrates such as aniline, p-aminophenol, hydroquinone, resorcinol, catechol, and paracetamol by means of hydrogen peroxide. The substrate spectrum overlaps with those of cytochrome P450s and plant peroxidases which are relevant in environmental analysis and drug monitoring. In M. rotula peroxygenase-based enzyme electrodes, the signal is generated by the reduction of electrode-active reaction products (e.g., p-benzoquinone and p-quinoneimine) with electro-enzymatic recycling of the analyte. In these enzyme electrodes, the signal reflects the conversion of all substrates thus representing an overall parameter in complex media. The performance of these sensors and their further development are discussed.
KW  - Unspecific peroxygenase
KW  - Cytochrome P450
KW  - Biosensors
KW  - Phenolic substances
Y1  - 2012
U6  - https://doi.org/10.1007/s00216-011-5497-y
SN  - 1618-2642
VL  - 402
IS  - 1
SP  - 405
EP  - 412
PB  - Springer
CY  - Heidelberg
ER  - 
TY  - JOUR
A1  - Bosserdt, Maria
A1  - Gajovic-Eichelman, Nenad
A1  - Scheller, Frieder W.
T1  - Modulation of direct electron transfer of cytochrome c by use of a molecularly imprinted thin film
JF  - Analytical & bioanalytical chemistry
N2  - We describe the preparation of a molecularly imprinted polymer film (MIP) on top of a self-assembled monolayer (SAM) of mercaptoundecanoic acid (MUA) on gold, where the template cytochrome c (cyt c) participates in direct electron transfer (DET) with the underlying electrode. To enable DET, a non-conductive polymer film is electrodeposited from an aqueous solution of scopoletin and cyt c on to the surface of a gold electrode previously modified with MUA. The electroactive surface concentration of cyt c was 0.5 pmol cm(-2). In the absence of the MUA layer, no cyt c DET was observed and the pseudo-peroxidatic activity of the scopoletin-entrapped protein, assessed via oxidation of Ampliflu red in the presence of hydrogen peroxide, was only 30 % of that for the MIP on MUA. This result indicates that electrostatic adsorption of cyt c by the MUA-SAM substantially increases the surface concentration of cyt c during the electrodeposition step, and is a prerequisite for the productive orientation required for DET. After template removal by treatment with sulfuric acid, rebinding of cyt c to the MUA-MIP-modified electrode occurred with an affinity constant of 100,000 mol(-1) L, a value three times higher than that determined by use of fluorescence titration for the interaction between scopoletin and cyt c in solution. The DET of cyt c in the presence of myoglobin, lysozyme, and bovine serum albumin (BSA) reveals that the MIP layer suppresses the effect of competing proteins.
KW  - Cytochrome c
KW  - Molecularly imprinted polymer film
KW  - Mercaptoundecanoic acid
KW  - Direct electron transfer
KW  - Scopoletin (7-hydroxy-6-methoxycoumarin)
Y1  - 2013
U6  - https://doi.org/10.1007/s00216-013-7009-8
SN  - 1618-2642
VL  - 405
IS  - 20
SP  - 6437
EP  - 6444
PB  - Springer
CY  - Heidelberg
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  - Frasca, Stefano
A1  - von Graberg, Till
A1  - Feng, Jiu-Ju
A1  - Thomas, Arne
A1  - Smarsly, Bernd M.
A1  - Weidinger, Inez M.
A1  - Scheller, Frieder W.
A1  - Hildebrandt, Peter
A1  - Wollenberger, Ursula
T1  - Mesoporous indium tin oxide as a novel platform for bioelectronics
N2  - Stable immobilization and reversible electrochemistry of cytochrome c in a tranparent indium tin oxide film with a well-defined mesoporosity (mpITO) is demonstrated. the transparency and good conductivity, in combination with the large surface area of mpITO, allow the incorporation of a high amount of elelctroactive biomolecules and their electrochemical and spectroscopic investigation. UV/Vis and resonance Raman spectroscopy, in combination with direct protein voltammetry are employed for the characterization of cytochrome c immobilized in the mpITO and reveal no perturbant of the structural of the integrity of the redox protein. The potential of this modified material as a biosensor detection of superoxide anions is also demonstrated.
Y1  - 2010
UR  - http://www3.interscience.wiley.com/journal/122208635/home
U6  - https://doi.org/10.1002/cctc.201000047
SN  - 1867-3880
ER  - 
TY  - JOUR
A1  - Baeumner, Antje J.
A1  - Gauglitz, Guenter
A1  - Scheller, Frieder W.
T1  - Focus on bioanalysis
N2  - Editoria
Y1  - 2010
UR  - http://www.springerlink.com/content/100417
U6  - https://doi.org/10.1007/s00216-010-4203-9
SN  - 1618-2642
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  - Scheller, Frieder W.
T1  - Tribute to Guenter Gauglitz (Editorial)
Y1  - 2009
UR  - http://www.springerlink.com/content/100417
U6  - https://doi.org/10.1007/s00216-008-2548-0
SN  - 1618-2642
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  - Lisdat, Fred
A1  - Dronov, Roman
A1  - Möhwald, Helmuth
A1  - Scheller, Frieder W.
A1  - Kurth, Dirk G.
T1  - Self-assembly of electro-active protein architectures on electrodes for the construction of biomimetic signal chains
N2  - The layer-by-layer adsorption technique based on the consecutive deposition of oppositely charged species is for the preparation of protein multilayers with fully electro-active protein molecules. The methodology was established with cytochrome c and the polyelectrolyte sulfonated polyaniline (PASA). The technique is also useful for the construction of bi-protein architectures confining protein-protein communication to an electrode. Following natural examples of protein complexes with defined signal transfer, cytochrome c was arranged with enzymes such as xanthine oxidase, bilirubin oxidase, laccase, and sulfite oxidase in self-assembled multilayer architectures. Thus, biomimetic signal chains from the enzyme substrate via the enzyme and cytochrome c towards the electrode can be established. Communication between proteins immobilised in multiple layers on the electrode can be achieved by in situ generation of small shuttle molecules or more advantageously by direct interprotein electron transfer. This allows the construction of new sensing electrodes, the properties of which can be tuned by the number of deposited protein layers. The mechanism of electron transfer within such protein assemblies on gold electrodes will be discussed.
Y1  - 2009
UR  - http://xlink.rsc.org/jumptojournal.cfm?journal_code=CC
U6  - https://doi.org/10.1039/B813559b
SN  - 1359-7345
ER  - 
TY  - JOUR
A1  - Spricigo, Roberto
A1  - Richter, Claudia
A1  - Leimkühler, Silke
A1  - Gorton, Lo
A1  - Scheller, Frieder W.
A1  - Wollenberger, Ursula
T1  - Sulfite biosensor based on osmium redox polymer wired sulfite oxidase
N2  - A biosensor, based on a redoxactive osmium polymer and sulfite oxidase on screen-printed electrodes, is presented here as a promising method for the detection of sulfite. A catalytic oxidative current was generated when a sample containing sulfite was pumped over the carbon screen-printed electrode modified with osmium redox polymer wired sulfite oxidase. A stationary value was reached after approximately 50 s and a complete measurement lasted no more than 3 min. The electrode polarized at -0.1 V (vs. Ag vertical bar AgCl 1M KCl) permits minimizing the influence of interfering substances, since these compounds can be unspecific oxidized at higher potentials. Because of the good stability of the protein film on the electrode surface, a well functioning biosensor-flow system was possible to construct. The working stability and reproducibility were further enhanced by the addition of bovine serum albumin generating a more long-term stable and biocompatible protein environment. The optimized biosensor showed a stable signal for more than a week of operation and a coefficient of variation of 4.8% for 12 successive measurements. The lower limit of detection of the sensor was 0.5 mu M sulfite and the response was linear until 100 mu M. The high sensitivity permitted a 1:500 dilution of wine samples. The immobilization procedure and the operational conditions granted minimized interferences. Additionally, repeating the immobilization procedure to form several layers of wired SO further increased the sensitivity of such a sensor. Finally. the applicability of the developed sulfite biosensor was tested on real samples, such as white and red wines.
Y1  - 2010
UR  - http://www.sciencedirect.com/science/journal/09277757
U6  - https://doi.org/10.1016/j.colsurfa.2009.09.001
SN  - 0927-7757
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  - 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  - 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  - Wollenberger, Ursula
A1  - Neumann, B.
A1  - Scheller, Frieder W.
T1  - Enzyme and microbial sensors for environmental Monitoring
Y1  - 1993
ER  - 
TY  - JOUR
A1  - Scheller, Frieder W.
A1  - Kirstein, Dieter
A1  - Schubert, Florian
A1  - Pfeiffer, Dorothea
A1  - McNeil, C. J.
T1  - Enzymes in electrochemical biosensors
Y1  - 1993
ER  - 
TY  - JOUR
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
T1  - Enzyme activation for activator and enzyme activity measurement
Y1  - 1993
ER  - 
TY  - JOUR
A1  - Wollenberger, Ursula
A1  - Schubert, Florian
A1  - Pfeiffer, Dorothea
A1  - Scheller, Frieder W.
T1  - Enhancing biosensor performance using multienzyme systems
Y1  - 1993
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  - Scheller, Frieder W.
A1  - Wollenberger, Ursula
A1  - Schubert, Florian
A1  - Pfeiffer, Dorothea
A1  - Markower, Alexander
A1  - McNeil, C. J.
T1  - Multienzyme biosensors : coupled enzyme reactions and enzyme activation
Y1  - 1993
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  - Wollenberger, Ursula
A1  - Neumann, B.
A1  - Riedel, K.
A1  - Scheller, Frieder W.
T1  - Enzyme and microbial sensors for phosphate, phenols, pesticides and peroxides
Y1  - 1994
ER  - 
TY  - JOUR
A1  - Scheller, Frieder W.
A1  - Heiduschka, P.
T1  - Preparation of an electrode surface with a high density of binding sites by an electrochemical reduction of a poly (nitrophenol) film
Y1  - 1994
ER  - 
TY  - JOUR
A1  - Scheller, Frieder W.
A1  - Makower, Alexander
A1  - Ghindilis, A. L.
A1  - Bier, Frank Fabian
A1  - Ehrentreich-Förster, Eva
A1  - Wollenberger, Ursula
A1  - Bauer, Christian G.
A1  - Micheel, Burkhard
A1  - Pfeiffer, Dorothea
A1  - Szeponik, Jan
A1  - Michael, N.
A1  - Kaden, H.
T1  - Enzyme sensors for subnanomolar concentrations
Y1  - 1995
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  - Riedel, K.
A1  - Beyersdorf-Radeck, Baerbel
A1  - Neumann, B.
A1  - Scheller, Frieder W.
A1  - Schmid, Rolf D.
T1  - Microbial sensors for determination of aromatics and their chloro derivatives. Part III: Determination of chlorinated phenols using a biosensor containing Trichosporon beigelii (cutaneum)
Y1  - 1995
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  - 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  - 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  - 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  - Scheller, Frieder W.
A1  - Pfeiffer, Dorothea
A1  - Schubert, Florian
A1  - Wollenberger, Ursula
T1  - Enzyme - based electrodes
Y1  - 1995
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  - 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  - Wollenberger, Ursula
A1  - Hintsche, R.
A1  - Scheller, Frieder W.
T1  - Biosensors for analytical microsystems
Y1  - 1995
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  - Stancik, L.
A1  - Macholán, L.
A1  - Scheller, Frieder W.
T1  - Biosensing of tyrosinase inhibitors in nonaqueous solvents
Y1  - 1995
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  - Ghindilis, A. L.
A1  - Makower, Alexander
A1  - Scheller, Frieder W.
T1  - Potentiometric enzyme electrodes based on substrate recycling and mediatorless bioelectrocatalysis
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Ghindilis, A. L.
A1  - Makower, Alexander
A1  - Scheller, Frieder W.
T1  - Nanomolar determination of the ferrocene derivatives using a recycling enzyme electrode : development of the redox label immunoassay
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Ghindilis, A. L.
A1  - Makower, Alexander
A1  - Scheller, Frieder W.
T1  - Laccase - glucose dehydrogenase recycling enzyme electrode based on potentiometric mediatorless electrocatalytic detection
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  - Eremenko, A. V.
A1  - Makower, Alexander
A1  - Scheller, Frieder W.
T1  - Measurement of nanomolar diphenols by substrate recycling coupled to a pH- sensitive electrode
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Bauer, Christian G.
A1  - Eremenko, A. V.
A1  - Ehrentreich-Förster, Eva
A1  - Bier, Frank Fabian
A1  - Makower, Alexander
A1  - Halsall, H. B.
A1  - Heineman, W. R.
A1  - Scheller, Frieder W.
T1  - Zeptomole-detecting biosensor for alkaline phosphatase in an electroche mical immunoassay for 2,4- dichlorophenoacetic acid
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Makower, Alexander
A1  - Eremenko, A. V.
A1  - Streffer, Katrin
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
T1  - Tyrosinase-glucose dehydrogenase substrate-recycling biosensor : a highly sensitive measurement of phenolic compounds
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Bier, Frank Fabian
A1  - Ehrentreich-Förster, Eva
A1  - Bauer, Christian G.
A1  - Scheller, Frieder W.
T1  - High sensitive competitive immunodetection of 2,4-dichlorophenoxyacetic acid using enzymatic amplification with electrochemical detection
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Wollenberger, Ursula
A1  - Schubert, Florian
A1  - Pfeiffer, Dorothea
A1  - Scheller, Frieder W.
T1  - Recycling sensors based on kinases : proceedings of Mosbach Symposion on Biochemical Technology
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Kaisheva, A.
A1  - Iliev, I.
A1  - Kazareva, R.
A1  - Christov, S.
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
T1  - Enzyme/gas diffusion electrodes for determination of phenol
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Bier, Frank Fabian
A1  - Ehrentreich-Förster, Eva
A1  - Scheller, Frieder W.
A1  - Makower, Alexander
A1  - Eremenko, A. V.
A1  - Wollenberger, Ursula
A1  - Bauer, Christian G.
A1  - Pfeiffer, Dorothea
A1  - Micheel, Burkhard
T1  - Ultrasensitive biosensors
Y1  - 1996
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  - 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  - 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  - Welzel, H.-P.
A1  - Kossmehl, G.
A1  - Engelmann, G.
A1  - Neumann, B.
A1  - Wollenberger, Ursula
A1  - Scheller, Frieder W.
A1  - Schröder, W.
T1  - Reactive groups on polymer covered electrodes, 4. Lactate-oxidase-biosensor based on electrodes modifies by polyphiophene
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Scheller, Frieder W.
T1  - New recognition elements for bioanalytics
Y1  - 1996
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  - Stöcklein, Walter F. M.
A1  - Scheller, Frieder W.
T1  - Laccase : a marker enzyme for solvent modified immunoassays
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Scheller, Frieder W.
A1  - Wollenberger, Ursula
A1  - Pfeiffer, Dorothea
A1  - Schubert, Florian
T1  - Overview of biosensor technology : proceedings of Mosbach Symposion on Biochemical Technology
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Bier, Frank Fabian
A1  - Scheller, Frieder W.
T1  - Label-free observation of DNA-hybridisation and endonuclease activity on a wave guide surface using a grating coupler
Y1  - 1996
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  - 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  - Wollenberger, Ursula
A1  - Lisdat, Fred
A1  - Scheller, Frieder W.
T1  - Enzymatic substrade recycling electrodes
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  - Scheller, Frieder W.
A1  - Schubert, Frank
A1  - Federowitz, J.
T1  - Present state and frontiers in biosensorics
Y1  - 1997
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  - 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  - 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  - 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  - Szeponik, Jan
A1  - Möller, B.
A1  - Pfeiffer, Dorothea
A1  - Lisdat, Fred
A1  - Wollenberger, Ursula
A1  - Makower, Alexander
A1  - Scheller, Frieder W.
T1  - Ultrasensitive bienzyme sensor for adrenaline
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Xie, B.
A1  - Tang, X.
A1  - Wollenberger, Ursula
A1  - Johansson, G.
A1  - Gorton, Lo
A1  - Scheller, Frieder W.
A1  - Danielsson, B.
T1  - Hybrid biosensor for simultaneous electrochemical and thermal detection
Y1  - 1997
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  - 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  - 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  - 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  - 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  - 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  - 
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  - Schulmeister, Thomas
A1  - Rose, Jürgen
A1  - Scheller, Frieder W.
T1  - Mathematical modelling of exponential amplification in membrane-based enzyme sensors
Y1  - 1997
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  - Scheller, Frieder W.
A1  - Pfeiffer, Dorothea
T1  - Commercial devices based on amperometric biosensors
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Bier, Frank Fabian
A1  - Kleinjung, Frank
A1  - Scheller, Frieder W.
T1  - Real time measurement of nucleic acid hybridization using evanescent wave sensors - step towards the genosensor
Y1  - 1997
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  - Scheller, Frieder W.
A1  - Pfeiffer, Dorothea
A1  - Lisdat, Fred
A1  - Bauer, Christian G.
A1  - Gajovic, Nenad
T1  - Enzyme biosensors based on oxygen detection
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Scheller, Frieder W.
A1  - Kleinjung, Frank
A1  - Bier, Frank Fabian
A1  - Markower, Alexander
A1  - Neumann, Barbara
A1  - Wollenberger, Ursula
A1  - Kurochkin, Iliya N.
A1  - Eremenko, Arkadi V.
A1  - Barmin, Anatoli V.
A1  - Klußmann, Sven
A1  - Fürste, Jens-Peter
A1  - Erdmann, Volker A.
A1  - Mansuy, D.
T1  - New recognition elements in biosensing
Y1  - 1998
ER  -