@article{MuribYeapMartensetal.2014, author = {Murib, Mohammed Sharif and Yeap, Weng-Siang and Martens, Daan and Bienstman, Peter and Ceuninck, Ward de and Grinsven, Bart van and Sch{\"o}ning, Michael Josef and Michiels, Luc and Haenen, Ken and Ameloot, Marcel and Serpeng{\"u}zel, Ali and Wagner, Patrick}, title = {Photonic detection and characterization of DNA using sapphire microspheres}, series = {Journal of biomedical optics}, volume = {19}, journal = {Journal of biomedical optics}, number = {9}, publisher = {SPIE}, address = {Bellingham}, issn = {1560-2281 (E-Journal); 1083-3668 (Print)}, doi = {10.1117/1.JBO.19.9.097006}, pages = {097006}, year = {2014}, abstract = {A microcavity-based deoxyribonucleic acid (DNA) optical biosensor is demonstrated for the first time using synthetic sapphire for the optical cavity. Transmitted and elastic scattering intensity at 1510 nm are analyzed from a sapphire microsphere (radius 500  μm, refractive index 1.77) on an optical fiber half coupler. The 0.43 nm angular mode spacing of the resonances correlates well with the optical size of the sapphire sphere. Probe DNA consisting of a 36-mer fragment was covalently immobilized on a sapphire microsphere and hybridized with a 29-mer target DNA. Whispering gallery modes (WGMs) were monitored before the sapphire was functionalized with DNA and after it was functionalized with single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA). The shift in WGMs from the surface modification with DNA was measured and correlated well with the estimated thickness of the add-on DNA layer. It is shown that ssDNA is more uniformly oriented on the sapphire surface than dsDNA. In addition, it is shown that functionalization of the sapphire spherical surface with DNA does not affect the quality factor (Q≈104) of the sapphire microspheres. The use of sapphire is especially interesting because this material is chemically resilient, biocompatible, and widely used for medical implants.}, language = {en} } @article{MuschallikKippReckeretal.2020, author = {Muschallik, Lukas and Kipp, Carina Ronja and Recker, Inga and Bongaerts, Johannes and Pohl, Martina and Gelissen, Melanie and Sch{\"o}ning, Michael Josef and Selmer, Thorsten and Siegert, Petra}, title = {Synthesis of α-hydroxy ketones and vicinal diols with the Bacillus licheniformis DSM 13T butane-2, 3-diol dehydrogenase}, series = {Journal of Biotechnology}, volume = {202}, journal = {Journal of Biotechnology}, number = {Vol. 324}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {2590-1559}, doi = {10.1016/j.jbiotec.2020.09.016}, pages = {61 -- 70}, year = {2020}, abstract = {The enantioselective synthesis of α-hydroxy ketones and vicinal diols is an intriguing field because of the broad applicability of these molecules. Although, butandiol dehydrogenases are known to play a key role in the production of 2,3-butandiol, their potential as biocatalysts is still not well studied. Here, we investigate the biocatalytic properties of the meso-butanediol dehydrogenase from Bacillus licheniformis DSM 13T (BlBDH). The encoding gene was cloned with an N-terminal StrepII-tag and recombinantly overexpressed in E. coli. BlBDH is highly active towards several non-physiological diketones and α-hydroxyketones with varying aliphatic chain lengths or even containing phenyl moieties. By adjusting the reaction parameters in biotransformations the formation of either the α-hydroxyketone intermediate or the diol can be controlled.}, language = {en} } @article{MuschallikMolinnusBongaertsetal.2017, author = {Muschallik, Lukas and Molinnus, Denise and Bongaerts, Johannes and Pohl, Martina and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Siegert, Petra and Selmer, Thorsten}, title = {(R,R)-Butane-2,3-diol Dehydrogenase from Bacillus clausii DSM 8716T: Cloning and Expression of the bdhA-Gene, and Initial Characterization of Enzyme}, series = {Journal of Biotechnology}, volume = {258}, journal = {Journal of Biotechnology}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0168-1656}, doi = {10.1016/j.jbiotec.2017.07.020}, pages = {41 -- 50}, year = {2017}, abstract = {The gene encoding a putative (R,R)-butane-2,3-diol dehydrogenase (bdhA) from Bacillus clausii DSM 8716T was isolated, sequenced and expressed in Escherichia coli. The amino acid sequence of the encoded protein is only distantly related to previously studied enzymes (identity 33-43\%) and exhibited some uncharted peculiarities. An N-terminally StrepII-tagged enzyme variant was purified and initially characterized. The isolated enzyme catalyzed the (R)-specific oxidation of (R,R)- and meso-butane-2,3-diol to (R)- and (S)-acetoin with specific activities of 12 U/mg and 23 U/mg, respectively. Likewise, racemic acetoin was reduced with a specific activity of up to 115 U/mg yielding a mixture of (R,R)- and meso-butane-2,3-diol, while the enzyme reduced butane-2,3-dione (Vmax 74 U/mg) solely to (R,R)-butane-2,3-diol via (R)-acetoin. For these reactions only activity with the co-substrates NADH/NAD+ was observed. The enzyme accepted a selection of vicinal diketones, α-hydroxy ketones and vicinal diols as alternative substrates. Although the physiological function of the enzyme in B. clausii remains elusive, the data presented herein clearly demonstrates that the encoded enzyme is a genuine (R,R)-butane-2,3-diol dehydrogenase with potential for applications in biocatalysis and sensor development.}, language = {en} } @article{MuschallikMolinnusJablonskietal.2020, author = {Muschallik, Lukas and Molinnus, Denise and Jablonski, Melanie and Kipp, Carina Ronja and Bongaerts, Johannes and Pohl, Martina and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Selmer, Thorsten and Siegert, Petra}, title = {Synthesis of α-hydroxy ketones and vicinal (R, R)-diols by Bacillus clausii DSM 8716ᵀ butanediol dehydrogenase}, series = {RSC Advances}, volume = {10}, journal = {RSC Advances}, publisher = {Royal Society of Chemistry (RSC)}, address = {Cambridge}, issn = {2046-2069}, doi = {10.1039/D0RA02066D}, pages = {12206 -- 12216}, year = {2020}, abstract = {α-hydroxy ketones (HK) and 1,2-diols are important building blocks for fine chemical synthesis. Here, we describe the R-selective 2,3-butanediol dehydrogenase from B. clausii DSM 8716ᵀ (BcBDH) that belongs to the metal-dependent medium chain dehydrogenases/reductases family (MDR) and catalyzes the selective asymmetric reduction of prochiral 1,2-diketones to the corresponding HK and, in some cases, the reduction of the same to the corresponding 1,2-diols. Aliphatic diketones, like 2,3-pentanedione, 2,3-hexanedione, 5-methyl-2,3-hexanedione, 3,4-hexanedione and 2,3-heptanedione are well transformed. In addition, surprisingly alkyl phenyl dicarbonyls, like 2-hydroxy-1-phenylpropan-1-one and phenylglyoxal are accepted, whereas their derivatives with two phenyl groups are not substrates. Supplementation of Mn²⁺ (1 mM) increases BcBDH's activity in biotransformations. Furthermore, the biocatalytic reduction of 5-methyl-2,3-hexanedione to mainly 5-methyl-3-hydroxy-2-hexanone with only small amounts of 5-methyl-2-hydroxy-3-hexanone within an enzyme membrane reactor is demonstrated.}, language = {en} } @article{NaetherAugerPoghossianetal.2004, author = {N{\"a}ther, Niko and Auger, V. and Poghossian, Arshak and Koudelka-Hep, M. and Sch{\"o}ning, Michael Josef}, title = {A miniaturized flow-through cell in SU-8 technique for EIS sensors}, series = {Biomedizinische Technik. 49 (2004), H. 2}, journal = {Biomedizinische Technik. 49 (2004), H. 2}, isbn = {0932-4666}, pages = {994 -- 995}, year = {2004}, language = {en} } @article{NaetherBergerEmmerichetal.2008, author = {N{\"a}ther, Niko and Berger, J{\"o}rg and Emmerich, R{\"u}diger and Friedrich, P. and Henkel, H. and Sch{\"o}ning, Michael Josef}, title = {H2O2-Konzentrationsbestimmung f{\"u}r die Prozessgasanalytik mittels eines kalorimetrischen Sensoraufbaus}, series = {Sensoren und Messsysteme 2008 : 14. Fachtagung Ludwigsburg, 11. und 12. M{\"a}rz 2008 / VDI/VDE-Gesellschaft Mess- und Automatisierungstechnik}, journal = {Sensoren und Messsysteme 2008 : 14. Fachtagung Ludwigsburg, 11. und 12. M{\"a}rz 2008 / VDI/VDE-Gesellschaft Mess- und Automatisierungstechnik}, publisher = {VDI-Verl.}, address = {D{\"u}sseldorf}, isbn = {978-3-18-092011-5}, pages = {783 -- 792}, year = {2008}, language = {de} } @article{NaetherBergerEmmerichetal.2007, author = {N{\"a}ther, Niko and Berger, J{\"o}rg and Emmerich, R{\"u}diger and Friedrich, Peter and Henkel, Hartmut and Schneider, Andreas and Sch{\"o}ning, Michael Josef}, title = {Entwicklung einer kalorimetrischen H2O2-Gassensoranordnung f{\"u}r die Prozessgaskontrolle}, series = {8. Dresdner Sensor-Symposium : Sensoren f{\"u}r Umwelt, Klima und Sicherheit, Biosensoren und Biosysteme, Sensoren und Sensorsysteme f{\"u}r die Prozesstechnik, Trends in der Sensortechnik, Materialentwicklung f{\"u}r die Sensorik; 8. Dresdner Sensor-Symposium, 10. - 12. Dezember 2007, Dresden / Gerald Gerlach ... (Hg.)}, journal = {8. Dresdner Sensor-Symposium : Sensoren f{\"u}r Umwelt, Klima und Sicherheit, Biosensoren und Biosysteme, Sensoren und Sensorsysteme f{\"u}r die Prozesstechnik, Trends in der Sensortechnik, Materialentwicklung f{\"u}r die Sensorik; 8. Dresdner Sensor-Symposium, 10. - 12. Dezember 2007, Dresden / Gerald Gerlach ... (Hg.)}, publisher = {TUDpress, Verl. der Wissenschaften}, address = {Dresden}, isbn = {978-3-940046-45-1}, pages = {261 -- 264}, year = {2007}, language = {de} } @article{NaetherEmmerichBergeretal.2006, author = {N{\"a}ther, Niko and Emmerich, R{\"u}diger and Berger, J{\"o}rg and Friedrich, Peter and Henkel, Hartmut and Schneider, Andreas and Sch{\"o}ning, Michael Josef}, title = {A novel gas-phase hydrogen peroxide sensor basing on a combined physical/chemical transduction mechanism}, series = {Nanofunctional materials, nanostructures, and novel devices for biological and chemical detection : November 27 - December 1, 2006, Boston, Massachusetts, USA ; [at the 2006 MRS Fall Meeting].}, journal = {Nanofunctional materials, nanostructures, and novel devices for biological and chemical detection : November 27 - December 1, 2006, Boston, Massachusetts, USA ; [at the 2006 MRS Fall Meeting].}, publisher = {Materials Research Soc.}, address = {Warrendale, Pa.}, isbn = {978-1-60423-407-7}, pages = {63 -- 68}, year = {2006}, language = {en} } @article{NaetherHenkelSchneideretal.2009, author = {N{\"a}ther, Niko and Henkel, Hartmut and Schneider, Andreas and Sch{\"o}ning, Michael Josef}, title = {Investigation of different catalytically active and passive materials for realising a hydrogen peroxide gas sensor}, series = {physica status solidi (a) . 206 (2009), H. 3}, journal = {physica status solidi (a) . 206 (2009), H. 3}, publisher = {Wiley}, address = {Weinheim}, isbn = {1862-6319}, pages = {449 -- 454}, year = {2009}, language = {en} } @inproceedings{NaetherJuarezEmmerichetal.2006, author = {N{\"a}ther, Niko and Ju{\´a}rez, Leon M. and Emmerich, R{\"u}diger and Berger, J{\"o}rg and Friedrich, Peter and Sch{\"o}ning, Michael Josef}, title = {Detection of hydrogen peroxide (H2O2) at exposed temperatures for industrial processes}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:a96-opus-1418}, year = {2006}, abstract = {An H2O2 sensor for the application in industrial sterilisation processes has been developed. Therefore, automated sterilisation equipment at laboratory scale has been constructed using parts from industrial sterilisation facilities. In addition, a software tool has been developed for the control of the sterilisation equipment at laboratory scale. First measurements with the developed sensor set-up as part of the sterilisation equipment have been performed and the sensor has been physically characterised by optical microscopy and SEM.}, subject = {Biosensor}, language = {en} }