@article{ZhangYarmanErdossyetal.2018,
  author    = {Zhang, Xiaorong and Yarman, Aysu and Erdossy, Julia and Katz, Sagie and Zebger, Ingo and Jetzschmann, Katharina J. and Altintas, Zeynep and Wollenberger, Ulla and Gyurcsanyi, Robert E. and Scheller, Frieder W.},
  title     = {Electrosynthesized MIPs for transferrin},
  series = {Biosensors and bioelectronics : the principal international journal devoted to research, design development and application of biosensors and bioelectronics},
  volume    = {105},
  journal   = {Biosensors and bioelectronics : the principal international journal devoted to research, design development and application of biosensors and bioelectronics},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0956-5663},
  doi       = {10.1016/j.bios.2018.01.011},
  pages     = {29 -- 35},
  year      = {2018},
  abstract  = {Molecularly imprinted polymer (MP) nanofilrns for transferrin (Trf) have been synthesized on gold surfaces by electro-polymerizing the functional monomer scopoletin in the presence of the protein target or around pre-adsorbed Trf. As determined by atomic force microscopy (AFM) the film thickness was comparable with the molecular dimension of the target. The target (re)binding properties of the electro-synthesized MIP films was evaluated by cyclic voltammetry (CV) and square wave voltammetry (SWV) through the target-binding induced permeability changes of the MIP nanofilms to the ferricyanide redox marker, as well as by surface plasmon resonance (SPR) and surface enhanced infrared absorption spectroscopy (SEIRAS) of the immobilized protein molecules. For Trf a linear concentration dependence in the lower micromolar range and an imprinting factor of similar to 5 was obtained by SWV and SPR. Furthermore, non-target proteins including the iron-free apo-Trf were discriminated by pronounced size and shape specificity. Whilst it is generally assumed that the rebinding of the target or of cross-reacting proteins exclusively takes place at the polymer here we considered also the interaction of the protein molecules with the underlying gold transducers. We demonstrate by SWV that adsorption of proteins suppresses the signal of the redox marker even at the bare gold surface and by SEIRAS that the treatment of the MIP with proteinase K or NaOH only partially removes the target protein. Therefore, we conclude that when interpreting binding of proteins to directly MIP-covered gold electrodes the interactions between the protein and the gold surface should also be considered.},
  language  = {en}
}
@article{ZhangCasertaYarmanetal.2021,
  author    = {Zhang, Xiaorong and Caserta, Giorgio and Yarman, Aysu and Supala, Eszter and Tadjoung Waffo, Armel Franklin and Wollenberger, Ulla and Gyurcsanyi, Robert E. and Zebger, Ingo and Scheller, Frieder W.},
  title     = {"Out of Pocket" protein binding},
  series = {Chemosensors},
  volume    = {9},
  journal   = {Chemosensors},
  number    = {6},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2227-9040},
  doi       = {10.3390/chemosensors9060128},
  pages     = {13},
  year      = {2021},
  abstract  = {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.},
  language  = {en}
}
@article{YarmanWollenbergerScheller2013,
  author    = {Yarman, Aysu and Wollenberger, Ursula and Scheller, Frieder W.},
  title     = {Sensors based on cytochrome P450 and CYP mimicking systems},
  series = {ELECTROCHIMICA ACTA},
  volume    = {110},
  journal   = {ELECTROCHIMICA ACTA},
  publisher = {PERGAMON-ELSEVIER SCIENCE LTD},
  address   = {OXFORD},
  issn      = {0013-4686},
  doi       = {10.1016/j.electacta.2013.03.154},
  pages     = {63 -- 72},
  year      = {2013},
  abstract  = {Cytochrome P450 enzymes (CYPs) act on more than 90 percent of all drugs currently on the market. The catalytic cycle requires electron supply to the heme iron in the presence of oxygen. Electrochemistry allows to characterise the reaction mechanism of these redox enzymes by observing the electron transfer in real time. According to the number of publications on protein electrochemistry CYP has the third position after glucose oxidase and cytochrome c. CYP based enzyme electrodes for the quantification of drugs, metabolites or pesticides have been developed using different iso-enzymes. A crucial step in the sensor development is the efficiency of coupling the biocatalytic systems with the electrode is. In the 1970s the direct electron transfer of heme and heme peptides called microperoxidases (MPs) was used as model of oxidoreductases. They exhibit a broad substrate spectrum including hydroxylation of selected aromatic substrates, demethylation and epoxidation by means of hydrogen peroxide. It overlaps with that of P450 making heme and MPs to alternate recognition elements in biosensors for the detection of typical CYP substrates. In these enzyme electrodes the signal is generated by the conversion of all substrates thus representing in complex media an overall parameter. By combining the biocatalytic substrate conversion with selective binding to a molecularly imprinted polymer layer the specificity has been improved. Here we discuss different approaches of biosensors based on CYP, microperoxidases and catalytically active MIPs and discuss their potential as recognition elements in biosensors. The performance of these sensors and their further development are discussed. (C) 2013 Elsevier Ltd. All rights reserved.},
  language  = {en}
}
@article{YarmanSchulzSygmundetal.2014,
  author    = {Yarman, Aysu and Schulz, Christopher and Sygmund, Cristoph and Ludwig, Roland and Gorton, Lo and Wollenberger, Ursula and Scheller, Frieder W.},
  title     = {Third generation ATP sensor with enzymatic analyte recycling},
  series = {Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis},
  volume    = {26},
  journal   = {Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis},
  number    = {9},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1040-0397},
  doi       = {10.1002/elan.201400231},
  pages     = {2043 -- 2048},
  year      = {2014},
  abstract  = {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).},
  language  = {en}
}
@misc{YarmanScheller2020,
  author    = {Yarman, Aysu and Scheller, Frieder W.},
  title     = {How reliable is the electrochemical readout of MIP sensors?},
  series = {Sensors},
  volume    = {20},
  journal   = {Sensors},
  number    = {9},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {1424-8220},
  doi       = {10.3390/s20092677},
  pages     = {23},
  year      = {2020},
  abstract  = {Electrochemical methods offer the simple characterization of the synthesis of molecularly imprinted polymers (MIPs) and the readouts of target binding. The binding of electroinactive analytes can be detected indirectly by their modulating effect on the diffusional permeability of a redox marker through thin MIP films. However, this process generates an overall signal, which may include nonspecific interactions with the nonimprinted surface and adsorption at the electrode surface in addition to (specific) binding to the cavities. Redox-active low-molecular-weight targets and metalloproteins enable a more specific direct quantification of their binding to MIPs by measuring the faradaic current. The in situ characterization of enzymes, MIP-based mimics of redox enzymes or enzyme-labeled targets, is based on the indication of an electroactive product. This approach allows the determination of both the activity of the bio(mimetic) catalyst and of the substrate concentration.},
  language  = {en}
}
@misc{YarmanScheller2020,
  author    = {Yarman, Aysu and Scheller, Frieder W.},
  title     = {How reliable is the electrochemical readout of MIP-sensors?},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe},
  number    = {960},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-47160},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-471608},
  pages     = {25},
  year      = {2020},
  abstract  = {Electrochemical methods offer the simple characterization of the synthesis of molecularly imprinted polymers (MIPs) and the readouts of target binding. The binding of electroinactive analytes can be detected indirectly by their modulating effect on the diffusional permeability of a redox marker through thin MIP films. However, this process generates an overall signal, which may include nonspecific interactions with the nonimprinted surface and adsorption at the electrode surface in addition to (specific) binding to the cavities. Redox-active low-molecular-weight targets and metalloproteins enable a more specific direct quantification of their binding to MIPs by measuring the faradaic current. The in situ characterization of enzymes, MIP-based mimics of redox enzymes or enzyme-labeled targets, is based on the indication of an electroactive product. This approach allows the determination of both the activity of the bio(mimetic) catalyst and of the substrate concentration.},
  language  = {en}
}
@article{YarmanScheller2013,
  author    = {Yarman, Aysu and Scheller, Frieder W.},
  title     = {Coupling biocatalysis with molecular imprinting in a biomimetic sensor},
  series = {Angewandte Chemie : a journal of the Gesellschaft Deutscher Chemiker ; International edition},
  volume    = {52},
  journal   = {Angewandte Chemie : a journal of the Gesellschaft Deutscher Chemiker ; International edition},
  number    = {44},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1433-7851},
  doi       = {10.1002/anie.201305368},
  pages     = {11521 -- 11525},
  year      = {2013},
  language  = {en}
}
@article{YarmanScheller2014,
  author    = {Yarman, Aysu and Scheller, Frieder W.},
  title     = {The first electrochemical MIP sensor for tamoxifen},
  series = {Sensors},
  volume    = {14},
  journal   = {Sensors},
  number    = {5},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {1424-8220},
  doi       = {10.3390/s140507647},
  pages     = {7647 -- 7654},
  year      = {2014},
  abstract  = {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.},
  language  = {en}
}
@article{YarmanScheller2016,
  author    = {Yarman, Aysu and Scheller, Frieder W.},
  title     = {MIP-esterase/Tyrosinase Combinations for Paracetamol and Phenacetin},
  series = {Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis},
  volume    = {28},
  journal   = {Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1040-0397},
  doi       = {10.1002/elan.201600042},
  pages     = {2222 -- 2227},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@misc{YarmanScheller2014,
  author    = {Yarman, Aysu and Scheller, Frieder W.},
  title     = {The first electrochemical MIP sensor for tamoxifen},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {1046},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-47617},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-476173},
  pages     = {10},
  year      = {2014},
  abstract  = {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.},
  language  = {en}
}
@article{YarmanNagelGajovicEichelmannetal.2011,
  author    = {Yarman, Aysu and Nagel, Thomas and Gajovic-Eichelmann, Nenad and Fischer, Anna and Wollenberger, Ursula and Scheller, Frieder W.},
  title     = {Bioelectrocatalysis by Microperoxidase-11 in a Multilayer Architecture of Chitosan Embedded Gold Nanoparticles},
  series = {Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis},
  volume    = {23},
  journal   = {Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis},
  number    = {3},
  publisher = {Wiley-Blackwell},
  address   = {Malden},
  issn      = {1040-0397},
  doi       = {10.1002/elan.201000535},
  pages     = {611 -- 618},
  year      = {2011},
  abstract  = {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.},
  language  = {en}
}
@article{YarmanKurbanoğluZebgeretal.2021,
  author    = {Yarman, Aysu and Kurbanoğlu, Sevin{\c{c}} and Zebger, Ingo and Scheller, Frieder W.},
  title     = {Simple and robust},
  series = {Sensors and actuators : B, Chemical : an international journal devoted to research and development of chemical transducers},
  volume    = {330},
  journal   = {Sensors and actuators : B, Chemical : an international journal devoted to research and development of chemical transducers},
  publisher = {Elsevier Science},
  address   = {Amsterdam [u.a.]},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2020.129369},
  pages     = {12},
  year      = {2021},
  abstract  = {A spectrum of 7562 publications on Molecularly Imprinted Polymers (MIPs) has been presented in literature within the last ten years (Scopus, September 7, 2020). Around 10 \% of the papers published on MIPs describe the recognition of proteins. The straightforward synthesis of MIPs is a significant advantage as compared with the preparation of enzymes or antibodies. MIPs have been synthesized from only one up to six functional monomers while proteins are made up of 20 natural amino acids. Furthermore, they can be synthesized against structures of low immunogenicity and allow multi-analyte measurements via multi-target synthesis. Electrochemical methods allow simple polymer synthesis, removal of the template and readout. Among the different sensor configurations electrochemical MIP-sensors provide the broadest spectrum of protein analytes. The sensitivity of MIP-sensors is sufficiently high for biomarkers in the sub-nanomolar region, nevertheless the cross-reactivity of highly abundant proteins in human serum is still a challenge. MIPs for proteins offer innovative tools not only for clinical and environmental analysis, but also for bioimaging, therapy and protein engineering.},
  language  = {en}
}
@misc{YarmanKurbanogluJetzschmannetal.2018,
  author    = {Yarman, Aysu and Kurbanoglu, Sevinc and Jetzschmann, Katharina J. and Ozkan, Sibel A. and Wollenberger, Ulla and Scheller, Frieder W.},
  title     = {Electrochemical MIP-Sensors for Drugs},
  series = {Current Medicinal Chemistry},
  volume    = {25},
  journal   = {Current Medicinal Chemistry},
  number    = {33},
  publisher = {Bentham Science Publishers LTD},
  address   = {Sharjah},
  issn      = {0929-8673},
  doi       = {10.2174/0929867324666171005103712},
  pages     = {4007 -- 4019},
  year      = {2018},
  abstract  = {In order to replace bio-macromolecules by stable synthetic materials in separation techniques and bioanalysis biomimetic receptors and catalysts have been developed: Functional monomers are polymerized together with the target analyte and after template removal cavities are formed in the "molecularly imprinted polymer" (MIP) which resemble the active sites of antibodies and enzymes. Starting almost 80 years ago, around 1,100 papers on MIPs were published in 2016. Electropolymerization allows to deposit MIPs directly on voltammetric electrodes or chips for quartz crystal microbalance (QCM) and surface plasmon resonance (SPR). For the readout of MIPs for drugs amperometry, differential pulse voltammetry (DPV) and impedance spectroscopy (EIS) offer higher sensitivity as compared with QCM or SPR. Application of simple electrochemical devices allows both the reproducible preparation of MIP sensors, but also the sensitive signal generation. Electrochemical MIP-sensors for the whole arsenal of drugs, e.g. the most frequently used analgesics, antibiotics and anticancer drugs have been presented in literature and tested under laboratory conditions. These biomimetic sensors typically have measuring ranges covering the lower nano-up to millimolar concentration range and they are stable under extreme pH and in organic solvents like nonaqueous extracts.},
  language  = {en}
}
@misc{YarmanJetzschmannNeumannetal.2017,
  author    = {Yarman, Aysu and Jetzschmann, Katharina J. and Neumann, Bettina and Zhang, Xiaorong and Wollenberger, Ulla and Cordin, Aude and Haupt, Karsten and Scheller, Frieder W.},
  title     = {Enzymes as tools in MIP-sensors},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {1098},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-47464},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-474642},
  pages     = {18},
  year      = {2017},
  abstract  = {Molecularly imprinted polymers (MIPs) have the potential to complement antibodies in bioanalysis, are more stable under harsh conditions, and are potentially cheaper to produce. However, the affinity and especially the selectivity of MIPs are in general lower than those of their biological pendants. Enzymes are useful tools for the preparation of MIPs for both low and high-molecular weight targets: As a green alternative to the well-established methods of chemical polymerization, enzyme-initiated polymerization has been introduced and the removal of protein templates by proteases has been successfully applied. Furthermore, MIPs have been coupled with enzymes in order to enhance the analytical performance of biomimetic sensors: Enzymes have been used in MIP-sensors as tracers for the generation and amplification of the measuring signal. In addition, enzymatic pretreatment of an analyte can extend the analyte spectrum and eliminate interferences.},
  language  = {en}
}
@misc{YarmanJetzschmannNeumannetal.2017,
  author    = {Yarman, Aysu and Jetzschmann, Katharina J. and Neumann, Bettina and Zhang, Xiaorong and Wollenberger, Ulla and Cordin, Aude and Haupt, Karsten and Scheller, Frieder W.},
  title     = {Enzymes as Tools in MIP-Sensors},
  series = {Chemosensors},
  volume    = {5},
  journal   = {Chemosensors},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2227-9040},
  doi       = {10.3390/chemosensors5020011},
  pages     = {16},
  year      = {2017},
  abstract  = {Molecularly imprinted polymers (MIPs) have the potential to complement antibodies in bioanalysis, are more stable under harsh conditions, and are potentially cheaper to produce. However, the affinity and especially the selectivity of MIPs are in general lower than those of their biological pendants. Enzymes are useful tools for the preparation of MIPs for both low and high-molecular weight targets: As a green alternative to the well-established methods of chemical polymerization, enzyme-initiated polymerization has been introduced and the removal of protein templates by proteases has been successfully applied. Furthermore, MIPs have been coupled with enzymes in order to enhance the analytical performance of biomimetic sensors: Enzymes have been used in MIP-sensors as tracers for the generation and amplification of the measuring signal. In addition, enzymatic pretreatment of an analyte can extend the analyte spectrum and eliminate interferences.},
  language  = {en}
}
@article{YarmanGroebeNeumannetal.2012,
  author    = {Yarman, Aysu and Gr{\"o}be, Glenn and Neumann, Bettina and Kinne, Mathias and Gajovic-Eichelmann, Nenad and Wollenberger, Ursula and Hofrichter, Martin and Ullrich, Rene and Scheibner, Katrin and Scheller, Frieder W.},
  title     = {The aromatic peroxygenase from Marasmius rutola-a new enzyme for biosensor applications},
  series = {Analytical \& bioanalytical chemistry},
  volume    = {402},
  journal   = {Analytical \& bioanalytical chemistry},
  number    = {1},
  publisher = {Springer},
  address   = {Heidelberg},
  issn      = {1618-2642},
  doi       = {10.1007/s00216-011-5497-y},
  pages     = {405 -- 412},
  year      = {2012},
  abstract  = {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.},
  language  = {en}
}
@misc{YarmanDechtriratBosserdtetal.2015,
  author    = {Yarman, Aysu and Dechtrirat, Decha and Bosserdt, Maria and Jetzschmann, Katharina J. and Gajovic-Eichelmann, Nenad and Scheller, Frieder W.},
  title     = {Cytochrome c-derived hybrid systems based on moleculary imprinted polymers},
  series = {Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis},
  volume    = {27},
  journal   = {Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis},
  number    = {3},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1040-0397},
  doi       = {10.1002/elan.201400592},
  pages     = {573 -- 586},
  year      = {2015},
  abstract  = {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.},
  language  = {en}
}
@article{YarmanBadalyanGajovicEichelmannetal.2011,
  author    = {Yarman, Aysu and Badalyan, Artavazd and Gajovic-Eichelmann, Nenad and Wollenberger, Ursula and Scheller, Frieder W.},
  title     = {Enzyme electrode for aromatic compounds exploiting the catalytic activities of microperoxidase-11},
  series = {Biosensors and bioelectronics : the principal international journal devoted to research, design development and application of biosensors and bioelectronics},
  volume    = {30},
  journal   = {Biosensors and bioelectronics : the principal international journal devoted to research, design development and application of biosensors and bioelectronics},
  number    = {1},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0956-5663},
  doi       = {10.1016/j.bios.2011.09.004},
  pages     = {320 -- 323},
  year      = {2011},
  abstract  = {Microperoxidase-11 (MR-11) which has been immobilised in a matrix of chitosan-embedded gold nanoparticles on the surface of a glassy carbon electrode catalyzes the conversion of aromatic substances. This peroxide-dependent catalysis of microperoxidase has been applied in an enzyme electrode for the first time to indicate aromatic compounds such as aniline. 4-fluoroaniline, catechol and p-aminophenol. The electrode signal is generated by the cathodic reduction of the quinone or quinoneimine which is formed in the presence of both MP-II and peroxide from the substrate. The same sensor principle will be extended to aromatic drugs.},
  language  = {en}
}
@article{XieTangWollenbergeretal.1997,
  author    = {Xie, B. and Tang, X. and Wollenberger, Ursula and Johansson, G. and Gorton, Lo and Scheller, Frieder W. and Danielsson, B.},
  title     = {Hybrid biosensor for simultaneous electrochemical and thermal detection},
  year      = {1997},
  language  = {en}
}
@article{WuWollenbergerHofrichteretal.2011,
  author    = {Wu, Yunhua and Wollenberger, Ursula and Hofrichter, Martin and Ullrich, Rene and Scheibner, Katrin and Scheller, Frieder W.},
  title     = {Direct electron transfer of Agrocybe aegerita peroxygenase at electrodes modified with chitosan-capped Au nanoparticles and its bioelectrocatalysis to aniline},
  series = {Sensors and actuators : B, Chemical},
  volume    = {160},
  journal   = {Sensors and actuators : B, Chemical},
  number    = {1},
  publisher = {Elsevier},
  address   = {Lausanne},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2011.09.090},
  pages     = {1419 -- 1426},
  year      = {2011},
  abstract  = {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.},
  language  = {en}
}
@article{WollenbergerSchubertPfeifferetal.1996,
  author    = {Wollenberger, Ursula and Schubert, Florian and Pfeiffer, Dorothea and Scheller, Frieder W.},
  title     = {Recycling sensors based on kinases : proceedings of Mosbach Symposion on Biochemical Technology},
  year      = {1996},
  language  = {en}
}
@article{WollenbergerSchubertPfeifferetal.1993,
  author    = {Wollenberger, Ursula and Schubert, Florian and Pfeiffer, Dorothea and Scheller, Frieder W.},
  title     = {Enhancing biosensor performance using multienzyme systems},
  year      = {1993},
  language  = {en}
}
@article{WollenbergerScheller1993,
  author    = {Wollenberger, Ursula and Scheller, Frieder W.},
  title     = {Enzyme activation for activator and enzyme activity measurement},
  year      = {1993},
  language  = {en}
}
@book{WollenbergerRennebergBieretal.2003,
  author    = {Wollenberger, Ursula and Renneberg, Reinhard and Bier, Frank Fabian and Scheller, Frieder W.},
  title     = {Analytische Biochemie : eine praktische Einf{\"u}hrung in das Messen mit Biomolek{\"u}len},
  publisher = {John Wiley \& Sons},
  address   = {Hoboken},
  isbn      = {3-527-30166-6},
  pages     = {222 S.},
  year      = {2003},
  language  = {de}
}
@article{WollenbergerNeumannScheller1998,
  author    = {Wollenberger, Ursula and Neumann, B. and Scheller, Frieder W.},
  title     = {Development of a biomimetic alkane sensor f},
  year      = {1998},
  language  = {en}
}
@article{WollenbergerNeumannScheller1993,
  author    = {Wollenberger, Ursula and Neumann, B. and Scheller, Frieder W.},
  title     = {Enzyme and microbial sensors for environmental Monitoring},
  year      = {1993},
  language  = {en}
}
@article{WollenbergerNeumannRiedeletal.1994,
  author    = {Wollenberger, Ursula and Neumann, B. and Riedel, K. and Scheller, Frieder W.},
  title     = {Enzyme and microbial sensors for phosphate, phenols, pesticides and peroxides},
  year      = {1994},
  language  = {en}
}
@article{WollenbergerLisdatScheller1997,
  author    = {Wollenberger, Ursula and Lisdat, Fred and Scheller, Frieder W.},
  title     = {Enzymatic substrade recycling electrodes},
  year      = {1997},
  language  = {en}
}
@article{WollenbergerJinBernhardtetal.1998,
  author    = {Wollenberger, Ursula and Jin, Wen and Bernhardt, Rita and Lehmann, Claudia and St{\"o}cklein, Walter F. M. and Brigelius-Floh{\´e}, Regina and Scheller, Frieder W.},
  title     = {Funktionalisierung von Elektroden f{\"u}r den direkten heterogenen Elektrotransfer},
  year      = {1998},
  language  = {de}
}
@article{WollenbergerHintscheScheller1995,
  author    = {Wollenberger, Ursula and Hintsche, R. and Scheller, Frieder W.},
  title     = {Biosensors for analytical microsystems},
  year      = {1995},
  language  = {en}
}
@article{WollenbergerDrungilieneStoeckleinetal.1996,
  author    = {Wollenberger, Ursula and Drungiliene, A. and St{\"o}cklein, Walter F. M. and Kulys, J. and Scheller, Frieder W.},
  title     = {Direct electrocatalytic determination of dissolved peroxidases},
  year      = {1996},
  language  = {en}
}
@article{WollenbergerBistolasJungetal.2004,
  author    = {Wollenberger, Ursula and Bistolas, Nikitas and Jung, Christiane and Shumyantseva, V. V. and Ruzgas, T. and Scheller, Frieder W.},
  title     = {Elektroden-Design f{\"u}r elektronische Wechselwirkung mit Monooxygenasen},
  isbn      = {3-8047-2132-x},
  year      = {2004},
  language  = {de}
}
@article{WelzelKossmehlEngelmannetal.1996,
  author    = {Welzel, H.-P. and Kossmehl, G. and Engelmann, G. and Neumann, B. and Wollenberger, Ursula and Scheller, Frieder W. and Schr{\"o}der, W.},
  title     = {Reactive groups on polymer covered electrodes, 4. Lactate-oxidase-biosensor based on electrodes modifies by polyphiophene},
  year      = {1996},
  language  = {en}
}
@article{WelzelKossmehlEngelmannetal.1997,
  author    = {Welzel, H.-P. and Kossmehl, G. and Engelmann, G. and Neumann, B. and Wollenberger, Ursula and Scheller, Frieder W.},
  title     = {Electrochemical polymerization of functionalized thiohene derivatives for immobilization of proteins},
  year      = {1997},
  language  = {en}
}
@article{WarsinkeStancikMacholanetal.1998,
  author    = {Warsinke, Axel and Stancik, L. and Machol{\´a}n, L. and Pfeiffer, Dorothea and Scheller, Frieder W.},
  title     = {Biosensors for food analysis : application of biosensors to food requirements},
  isbn      = {0-85404-750-6},
  year      = {1998},
  language  = {en}
}
@article{WarsinkeBenkertScheller1996,
  author    = {Warsinke, Axel and Benkert, Alexander and Scheller, Frieder W.},
  title     = {Biomolecular modules for creatinine determination},
  year      = {1996},
  language  = {en}
}
@article{WarsinkeBenkertScheller2000,
  author    = {Warsinke, Axel and Benkert, Alexander and Scheller, Frieder W.},
  title     = {Electrochemical immunoassays},
  year      = {2000},
  language  = {en}
}
@article{VijgenboomVijgenboomTeppneretal.2001,
  author    = {Vijgenboom, E. and Vijgenboom, E. and Teppner, A. W. J. W. and Makower, Alexander and Scheller, Frieder W. and Canters, Gerard W. and Wollenberger, Ursula},
  title     = {Determination of phenolic compounds using recombinant tyrosinanse from Streptomyces antibioticus},
  year      = {2001},
  language  = {en}
}
@article{TellerHalamekMakoweretal.2006,
  author    = {Teller, C. and Halamek, Jan and Makower, Alexander and Fournier, Didier and Schulze, H. and Scheller, Frieder W.},
  title     = {A piezoelectric sensor with propidium as a recognition element for cholinesterases},
  doi       = {10.1016/j.snb.2005.02.053},
  year      = {2006},
  abstract  = {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},
  language  = {en}
}
@article{TanneJeoungPengetal.2015,
  author    = {Tanne, Johannes and Jeoung, Jae-Hun and Peng, Lei and Yarman, Aysu and Dietzel, Birgit and Schulz, Burkhard and Schad, Daniel and Dobbek, Holger and Wollenberger, Ursula and Bier, Frank Fabian and Scheller, Frieder W.},
  title     = {Direct Electron Transfer and Bioelectrocatalysis by a Hexameric, Heme Protein at Nanostructured Electrodes},
  series = {Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis},
  volume    = {27},
  journal   = {Electroanalysis : an international journal devoted to fundamental and practical aspects of electroanalysis},
  number    = {10},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1040-0397},
  doi       = {10.1002/elan.201500231},
  pages     = {2262 -- 2267},
  year      = {2015},
  abstract  = {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.},
  language  = {en}
}
@article{TadjoungWaffoYesildagCasertaetal.2018,
  author    = {Tadjoung Waffo, Armel Franklin and Yesildag, Cigdem and Caserta, Giorgio and Katz, Sagie and Zebger, Ingo and Lensen, Marga C. and Wollenberger, Ulla and Scheller, Frieder W. and Altintas, Zeynep},
  title     = {Fully electrochemical MIP sensor for artemisinin},
  series = {Sensors and actuators : B, Chemical},
  volume    = {275},
  journal   = {Sensors and actuators : B, Chemical},
  publisher = {Elsevier},
  address   = {Lausanne},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2018.08.018},
  pages     = {163 -- 173},
  year      = {2018},
  abstract  = {This study aims to develop a rapid, sensitive and cost-effective biomimetic electrochemical sensor for artemisinin determination in plant extracts and for pharmacokinetic studies. A novel molecularly imprinted polymer (MIP)based electrochemical sensor was developed by electropolymerization of o-phenylenediamine (o-PD) in the presence of artemisinin on gold wire surface for sensitive detection of artemisinin. The experimental parameters, including selection of functional monomer, polymerization conditions, template extraction after polymerization, influence of pH and buffer were all optimized. Every step of imprinted film synthesis were evaluated by employing voltammetry techniques, surface-enhanced infrared absorption spectroscopy (SEIRAS) and atomic force microscopy (AFM). The specificity was further evaluated by investigating non-specific artemisinin binding on non-imprinted polymer (NIP) surfaces and an imprinting factor of 6.8 was achieved. The artemisinin imprinted polymers using o-PD as functional monomer have provided highly stable and effective binding cavities for artemisinin. Cross-reactivity studies with drug molecules showed that the MIPs are highly specific for artemisinin. The influence of matrix effect was further investigated both in artificial plant matrix and diluted human serum. The results revealed a high affinity of artemisinin-MIP with dissociation constant of 7.3 x 10(-9) M and with a detection limit of 0.01 mu M and 0.02 mu M in buffer and plant matrix, respectively.},
  language  = {en}
}
@article{SzeponikMoellerPfeifferetal.1997,
  author    = {Szeponik, Jan and M{\"o}ller, B. and Pfeiffer, Dorothea and Lisdat, Fred and Wollenberger, Ursula and Makower, Alexander and Scheller, Frieder W.},
  title     = {Ultrasensitive bienzyme sensor for adrenaline},
  year      = {1997},
  language  = {en}
}
@article{StoellnerStoeckleinSchelleretal.2002,
  author    = {St{\"o}llner, Daniela and St{\"o}cklein, Walter F. M. and Scheller, Frieder W. and Warsinke, Axel},
  title     = {Membrane-immobilized haptoglobin as affinity matrix for a hemoglobin-A1c-immunosensor},
  year      = {2002},
  language  = {en}
}
@article{StoeckleinWarsinkeScheller1997,
  author    = {St{\"o}cklein, Walter F. M. and Warsinke, Axel and Scheller, Frieder W.},
  title     = {Organic solvent modified enzyme-liked immunoassay for the detection of triazine herbicides},
  year      = {1997},
  language  = {en}
}
@article{StoeckleinWarsinkeMicheeletal.1998,
  author    = {St{\"o}cklein, Walter F. M. and Warsinke, Axel and Micheel, Burkhard and Kempter, Gerhard and H{\"o}hne, Wolfgang and Scheller, Frieder W.},
  title     = {Diphenylurea hapten sensing with a monoclonal antibody and its Fab fragment : kinetic and thermodynamic investigations},
  year      = {1998},
  language  = {en}
}
@article{StoeckleinWarsinkeMicheeletal.1998,
  author    = {St{\"o}cklein, Walter F. M. and Warsinke, Axel and Micheel, Burkhard and H{\"o}hne, Wolfgang and Woller, Jochen and Kempter, Gerhard and Scheller, Frieder W.},
  title     = {Characterization of a monoclonal antibody and its Fab fragment against diphenylurea hapten with BIA},
  isbn      = {3-8154-3540-4},
  year      = {1998},
  language  = {en}
}
@article{StoeckleinWarsinkeMicheeletal.1997,
  author    = {St{\"o}cklein, Walter F. M. and Warsinke, Axel and Micheel, Burkhard and H{\"o}hne, Wolfgang and Woller, Jochen and Kempter, Gerhard and Scheller, Frieder W.},
  title     = {Detection of diphenylurea derivatives with biospecific interaction analysis (BIA) : Kinetic investigations},
  year      = {1997},
  language  = {en}
}
@article{StoeckleinSchellerAbuknesha1995,
  author    = {St{\"o}cklein, Walter F. M. and Scheller, Frieder W. and Abuknesha, Rhamadan},
  title     = {Effects of organic solvents on semicontinuous immunochemical detection of coumarin derivatives},
  year      = {1995},
  language  = {en}
}
@article{StoeckleinScheller1997,
  author    = {St{\"o}cklein, Walter F. M. and Scheller, Frieder W.},
  title     = {Enzymes and antibodies in organic media : analytical applications},
  year      = {1997},
  language  = {en}
}
@article{StoeckleinScheller1995,
  author    = {St{\"o}cklein, Walter F. M. and Scheller, Frieder W.},
  title     = {Einsatz von Enzymen und Antik{\"o}rpern in organischen L{\"o}sungsmitteln},
  year      = {1995},
  language  = {de}
}