@article{BenkertMicheelSchoessleretal.2001, author = {Benkert, Alexander and Micheel, Burkhard and Sch{\"o}ssler, W. and Warsinke, Axel}, title = {Mischen und gleich messen : creatinin spezifisch und einfach bestimmen mit den Size exclusion redox-labeled immunoassay}, year = {2001}, language = {de} } @phdthesis{BenkertSchellerSchoessleretal.2000, author = {Benkert, Alexander and Scheller, Frieder W. and Sch{\"o}ssler, W. and Micheel, Burkhard and Warsinke, Axel}, title = {Size exclusion redox-labeled immunoassay (SERI) : a new format for homogeneous amperometric creatinine determination}, year = {2000}, language = {en} } @article{ChenWarsinkeGajovicetal.2000, author = {Chen, Ziping and Warsinke, Axel and Gajovic, Nenad and Große, St. and Hu, J. and Kleber, H.-P. and Scheller, Frieder W.}, title = {A D-carnitine dehydrogenase electrode for the assessment of enantiomeric purity of L-carnitine preparations}, year = {2000}, language = {en} } @article{GajovicBinyaminWarsinkeetal.2000, author = {Gajovic, Nenad and Binyamin, Gary and Warsinke, Axel and Scheller, Frieder W. and Heller, A.}, title = {Operation of a miniature redox hydrogel-based pyruvate sensor in undiluted deoxygenated calf serum}, year = {2000}, language = {en} } @article{GajovicHabermuellerWarsinkeetal.1999, author = {Gajovic, Nenad and Haberm{\"u}ller, K. and Warsinke, Axel and Schuhmann, W. and Scheller, Frieder W.}, title = {A pyruvate oxidase electrode based on an electrochemically deposited redox polymer}, year = {1999}, language = {en} } @article{GajovicWarsinkeHuangetal.1999, author = {Gajovic, Nenad and Warsinke, Axel and Huang, T. and Schulmeister, Thomas and Scheller, Frieder W.}, title = {Characterization and mathematical modelling of a novel bienzyme electrode for L-malate with cofactor recycling}, year = {1999}, language = {en} } @article{GajovicWarsinkeScheller1997, author = {Gajovic, Nenad and Warsinke, Axel and Scheller, Frieder W.}, title = {Comparsion of two enzyme sequences for a novel L-malate biosensor}, year = {1997}, language = {en} } @article{GajovicWarsinkeScheller1995, author = {Gajovic, Nenad and Warsinke, Axel and Scheller, Frieder W.}, title = {A novel multienzyme electrode for the determination of citrate}, year = {1995}, language = {en} } @article{GajovicWarsinkeScheller1998, author = {Gajovic, Nenad and Warsinke, Axel and Scheller, Frieder W.}, title = {A bienzyme electrode for L-malate based on a novel and general design}, year = {1998}, language = {en} } @article{GriessnerHartigChristmannetal.2010, author = {Grießner, Matthias and Hartig, Dave and Christmann, Alexander and Ehrentreich-F{\"o}rster, Eva and Warsinke, Axel and Bier, Frank Fabian}, title = {Surface regeneration of microfluidic microarray printheads through plasma techniques}, issn = {0960-1317}, doi = {10.1088/0960-1317/20/3/037002}, year = {2010}, abstract = {This work describes a method for surface regeneration of microfluidic microarray printheads through plasma techniques. Modification procedures were chosen in a way to obtain high reproducibility with a minimum of time consumption. The idea behind this is a complete regeneration of a microarray printhead before or after usage to achieve best printing results over a typical print job. A sequence of low-pressure oxygen-plasma and plasma polymerization with hexamethyldisiloxane (HMDSO) was used to regenerate printheads. Proof of the concept is given through quality control performed with a spotter implemented CCD camera, contact angle measurements and a typical hybridization experiment. Stable printing results were obtained over 3000 activations showing that the presented method is suitable for treatment of microarray printheads.}, language = {en} } @article{GuhaWarsinkeTientcheuetal.2015, author = {Guha, S. and Warsinke, Axel and Tientcheu, Charles Merlin and Schmalz, K. and Meliani, C. and Wenger, Ch.}, title = {Label free sensing of creatinine using a 6 GHz CMOS near-field dielectric immunosensor}, series = {The analyst : the analytical journal of the Royal Society of Chemistry}, volume = {140}, journal = {The analyst : the analytical journal of the Royal Society of Chemistry}, number = {9}, publisher = {Royal Society of Chemistry}, address = {Cambridge}, issn = {0003-2654}, doi = {10.1039/c4an02194k}, pages = {3019 -- 3027}, year = {2015}, abstract = {In this work we present a CMOS high frequency direct immunosensor operating at 6 GHz (C-band) for label free determination of creatinine. The sensor is fabricated in standard 0.13 mu m SiGe:C BiCMOS process. The report also demonstrates the ability to immobilize creatinine molecules on a Si3N4 passivation layer of the standard BiCMOS/CMOS process, therefore, evading any further need of cumbersome post processing of the fabricated sensor chip. The sensor is based on capacitive detection of the amount of non-creatinine bound antibodies binding to an immobilized creatinine layer on the passivated sensor. The chip bound antibody amount in turn corresponds indirectly to the creatinine concentration used in the incubation phase. The determination of creatinine in the concentration range of 0.88-880 mu M is successfully demonstrated in this work. A sensitivity of 35 MHz/10 fold increase in creatinine concentration (during incubation) at the centre frequency of 6 GHz is gained by the immunosensor. The results are compared with a standard optical measurement technique and the dynamic range and sensitivity is of the order of the established optical indication technique. The C-band immunosensor chip comprising an area of 0.3 mm(2) reduces the sensing area considerably, therefore, requiring a sample volume as low as 2 mu l. The small analyte sample volume and label free approach also reduce the experimental costs in addition to the low fabrication costs offered by the batch fabrication technique of CMOS/BiCMOS process.}, language = {en} } @article{HalamekWollenbergerStoeckleinetal.2007, author = {Hal{\´a}mek, Jan and Wollenberger, Ursula and St{\"o}cklein, Walter F. M. and Warsinke, Axel and Scheller, Frieder W.}, title = {Signal amplification in immunoassays using labeling via boronic acid binding to the sugar moiety of immunoglobulin G : proof of concept for glycated hemoglobin}, issn = {0003-2719}, doi = {10.1080/00032710701327096}, year = {2007}, abstract = {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.}, language = {en} } @article{HuangWarsinkeKoroljovaSkorobogatkoetal.1999, author = {Huang, T. and Warsinke, Axel and Koroljova-Skorobogatko, O. V. and Makower, Alexander and Kuwana, T. and Scheller, Frieder W.}, title = {A bienzyme carbon paste electrode for the sensitive detection of NADPH and the measurement of glucose-6- phosphate dehydrogenase}, year = {1999}, language = {en} } @article{HuangWarsinkeKuwanaetal.1998, author = {Huang, T. and Warsinke, Axel and Kuwana, T. and Scheller, Frieder W.}, title = {The determination of L-phenylalanine based on a novel NADH-detecting biosensor}, year = {1998}, language = {en} } @article{KleinjungBeierWarsinkeetal.1997, author = {Kleinjung, Frank and Beier, Frank F. and Warsinke, Axel and Scheller, Frieder W.}, title = {Fibre-optic genosensor for specific determination of femtomolar DNA oligomers}, year = {1997}, language = {en} } @article{LettauGajovicEichelmannKwaketal.2004, author = {Lettau, Kristian and Gajovic-Eichelmann, N. and Kwak, Young-Keun and Scheller, Frieder W. and Warsinke, Axel}, title = {Hydroxylasen und katalytische Polymere f{\"u}r Biochips}, year = {2004}, language = {de} } @article{LettauWarsinkeKatterleetal.2006, author = {Lettau, Kristian and Warsinke, Axel and Katterle, Martin and Danielsson, Bengt and Scheller, Frieder W.}, title = {A bifunctional molecularly imprinted polymer (MIP): analysis of binding and catalysis by a thermistor}, doi = {10.1002/anie.200601796}, year = {2006}, abstract = {Binding or catalysis? Both can be distinguished with a molecularly imprinted polymer (MIP) by the different patterns of heat generation. The catalytically active sites, like in the corresponding enzyme, generate a steady-state temperature increase. Thus, enzyme-like catalysis and antibody-analogue binding are analyzed simultaneously in a bifunctional MIP for the first time (see scheme).}, language = {en} } @article{LettauWarsinkeLaschewskyetal.2004, author = {Lettau, Kristian and Warsinke, Axel and Laschewsky, Andr{\´e} and Mosbach, K. and Yilmaz, E. and Scheller, Frieder W.}, title = {An esterolytic imprinted polymer prepared via a silica-supported transition state analogue}, year = {2004}, abstract = {In this work we describe a new preparation method for an esterolytic imprinted polymer with catalytic sites on the surface. A template was prepared by immobilizing a transition state analogue (phosphoramidic acid derivative) of an esterolytic reaction within porous silica particles. Polymerization within the pores was carried out using 4- vinylimidazole as a functional monomer and divinylbenzene as a cross-linker. The polymer was released by dissolution of the silica support with hydrofluoric acid and catalytic properties were studied by incubation with three different 4- nitrophenylesters and spectrophotometric determination of the released 4-nitrophenol. For 4-nitrophenyl acetate an activity of 211 nmol min(-1) mg(-1) and a K-m value of 2.2 mmol L-1 was obtained}, language = {en} } @article{LiuWollenbergerHalameketal.2005, author = {Liu, Songqin and Wollenberger, Ursula and Halamek, Jan and Leupold, Eik and St{\"o}cklein, Walter F. M. and Warsinke, Axel and Scheller, Frieder W.}, title = {Affinity interaction betwen phenylboronic acid-carrying self-assembled monolayers and FAD or HRP}, year = {2005}, abstract = {A method is provided for the recognition of glycated molecules based on their binding affinities to boronate- carrying monolayers. The affinity interaction of flavin adenine dinucleotide (FAD) and horseradish peroxidase (HRP) with phenylboronic acid monolayers on gold was investigated by using voltammetric and microgravimetric methods. Conjugates of 3-aminopherrylboronic acid and 3,3'-dithiodipropionic acid di(N-hydroxysuccinimide ester) or 11-mercaptoundecanoic acid were prepared and self-assembled on gold surfaces to generate monolayers. FAD is bound to this modified sur-face and recognized by a pair of redox peaks with a formal potential of -0.433 V in a 0.1 m phosphate buffer solution, pH 6.5. Upon addition of a sugar to the buffer, the bound FAD could be replaced, indicating that the binding is reversible. Voltammetric, mass measurements, and photometric activity assays show that the HRP can also be bound to the interface. This binding is reversible, and HRP can be replaced by sorbitol or removed in acidic solution. The effects of pH, incubation time, and concentration of H2O2 were studied by comparing the catalytic reduction of H2O2 in the presence of the electron-donor thionine. The catalytic current of the HRP-loaded electrode was proportional to HRP concentrations in the incubation solution in the range between 5 mu g mL(-1) and 0.4 mg mL(-1) with a linear slope of 3.34 mu A mL mg(-1) and a correlation coefficient of 0.9945}, language = {en} } @article{LuetkecosmannWarsinkeTschoepeetal.2017, author = {L{\"u}tkecosmann, Steffi and Warsinke, Axel and Tsch{\"o}pe, Winfried and Eichler, R{\"u}diger and Hanack, Katja}, title = {A novel monoclonal antibody suitable for the detection of leukotriene B4}, series = {Biochemical and biophysical research communications}, volume = {482}, journal = {Biochemical and biophysical research communications}, number = {4}, publisher = {Elsevier}, address = {San Diego}, issn = {0006-291X}, doi = {10.1016/j.bbrc.2016.11.157}, pages = {1054 -- 1059}, year = {2017}, abstract = {Leukotriene B4 as an inflammatory mediator is an important biomarker for different respiratory diseases like asthma, chronic obstructive pulmonary disease or cystic lung fibrosis. Therefore the detection of LTB4 is helpful in the diagnosis of these pulmonary diseases. However, until now its determination in exhaled breath condensates suffers from problems of accuracy. Reasons for that could be improper sample collection and preparation methods of condensates and the lack of consistently assay specificity and reproducibility of the used immunoassay detection system. In this study we describe the development and the characterization of a specific monoclonal antibody (S27BC6) against LTB4, its use as molecular recognition element for the development of an enzyme-linked immunoassay to detect LTB4 and discuss possible future diagnostic applications.}, language = {en} }