@article{ErmelenkoYoshinobuMourzinaetal.2002, author = {Ermelenko, Y. and Yoshinobu, T. and Mourzina, Y. and Sch{\"o}ning, Michael Josef and Vlasov, Y. and Iwasaki, H.}, title = {The hybrid K+/Ca2+ sensor based on laser scanned silicon transducer for multi-component analysis}, series = {Proceedings of ICAS 2001, IUPAC [3rd] International Congress on Analytical Sciences 2001 : August 6 - 10, 2001, Waseda University, Tokyo}, journal = {Proceedings of ICAS 2001, IUPAC [3rd] International Congress on Analytical Sciences 2001 : August 6 - 10, 2001, Waseda University, Tokyo}, publisher = {Japan Society for Analytical Chemistry}, address = {Tokyo}, pages = {i777 -- i780}, year = {2002}, language = {en} } @article{ErmelenkoYoshinobuMourzinaetal.2003, author = {Ermelenko, Y. and Yoshinobu, T. and Mourzina, Y. and Sch{\"o}ning, Michael Josef and Furuichi, K. and Levichev, S. and Vlasov, Y. and Iwasaki, H.}, title = {The double K+/Ca2+ sensor based on laser scanned silicon transducer (LSST) for multicomponent analysis}, series = {Talanta. 59 (2003), H. 4}, journal = {Talanta. 59 (2003), H. 4}, isbn = {0039-9140}, pages = {785 -- 795}, year = {2003}, language = {en} } @article{ErmelenkoYoshinobuMourzinaetal.2002, author = {Ermelenko, Y. and Yoshinobu, T. and Mourzina, Y. and Furuichi, K. and Levichev, S. and Vlasov, Y. and Sch{\"o}ning, Michael Josef and Iwasaki, H.}, title = {Lithium sensor based on the laser scanning semiconductor transducer}, series = {Analytica Chimica Acta. 459 (2002), H. 1}, journal = {Analytica Chimica Acta. 459 (2002), H. 1}, issn = {0378-4304}, pages = {1 -- 9}, year = {2002}, language = {en} } @article{ErmelenkoYoshinobuMourzinaetal.2001, author = {Ermelenko, Y. and Yoshinobu, T. and Mourzina, Y. and Furuichi, K. and Iwasaki, H. and Vlasov, Y. and Sch{\"o}ning, Michael Josef}, title = {Technology of photocurable polymeric membranes for integrated LAPS}, series = {Proceedings of the 5th East Asian Conference on Chemical Sensors; the 33rd Chemical Sensor Symposium : December 4 - 7, 2001, Huis Ten Bosch, Sasebo-shi, Nagasaki, Japan / Japan Association of Chemical Sensors; the Electrochemical Society of Japan}, journal = {Proceedings of the 5th East Asian Conference on Chemical Sensors; the 33rd Chemical Sensor Symposium : December 4 - 7, 2001, Huis Ten Bosch, Sasebo-shi, Nagasaki, Japan / Japan Association of Chemical Sensors; the Electrochemical Society of Japan}, publisher = {Japan Association of Chemical Sensors}, address = {Kasuga, Fukuoka-ken}, pages = {66 -- 68}, year = {2001}, language = {en} } @article{ErmelenkoYoshinobuMourzinaetal.2002, author = {Ermelenko, Y. and Yoshinobu, T and Mourzina, Y. and Levichev, S. and Furuichi, K. and Vlasov, Y. and Sch{\"o}ning, Michael Josef and Iwasaki, H.}, title = {Photocurable membranes for ion-selective light-addressable potentiometric sensors}, series = {Sensors and Actuators B. 85 (2002), H. 1-2}, journal = {Sensors and Actuators B. 85 (2002), H. 1-2}, isbn = {0925-4005}, pages = {79 -- 85}, year = {2002}, language = {en} } @article{EngelmannSimsekShalabyetal.2024, author = {Engelmann, Ulrich M. and Simsek, Beril and Shalaby, Ahmed and Krause, Hans-Joachim}, title = {Key contributors to signal generation in frequency mixing magnetic detection (FMMD): an in silico study}, series = {Sensors}, volume = {24}, journal = {Sensors}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {10.3390/s24061945}, pages = {Artikel 1945}, year = {2024}, abstract = {Frequency mixing magnetic detection (FMMD) is a sensitive and selective technique to detect magnetic nanoparticles (MNPs) serving as probes for binding biological targets. Its principle relies on the nonlinear magnetic relaxation dynamics of a particle ensemble interacting with a dual frequency external magnetic field. In order to increase its sensitivity, lower its limit of detection and overall improve its applicability in biosensing, matching combinations of external field parameters and internal particle properties are being sought to advance FMMD. In this study, we systematically probe the aforementioned interaction with coupled N{\´e}el-Brownian dynamic relaxation simulations to examine how key MNP properties as well as applied field parameters affect the frequency mixing signal generation. It is found that the core size of MNPs dominates their nonlinear magnetic response, with the strongest contributions from the largest particles. The drive field amplitude dominates the shape of the field-dependent response, whereas effective anisotropy and hydrodynamic size of the particles only weakly influence the signal generation in FMMD. For tailoring the MNP properties and parameters of the setup towards optimal FMMD signal generation, our findings suggest choosing large particles of core sizes dc > 25 nm nm with narrow size distributions (σ < 0.1) to minimize the required drive field amplitude. This allows potential improvements of FMMD as a stand-alone application, as well as advances in magnetic particle imaging, hyperthermia and magnetic immunoassays.}, language = {en} } @article{EngelmannPourshahidiShalabyetal.2022, author = {Engelmann, Ulrich M. and Pourshahidi, Mohammad Ali and Shalaby, Ahmed and Krause, Hans-Joachim}, title = {Probing particle size dependency of frequency mixing magnetic detection with dynamic relaxation simulation}, series = {Journal of Magnetism and Magnetic Materials}, volume = {563}, journal = {Journal of Magnetism and Magnetic Materials}, number = {In progress, Art. No. 169965}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0304-8853}, doi = {10.1016/j.jmmm.2022.169965}, year = {2022}, abstract = {Biomedical applications of magnetic nanoparticles (MNP) fundamentally rely on the particles' magnetic relaxation as a response to an alternating magnetic field. The magnetic relaxation complexly depends on the interplay of MNP magnetic and physical properties with the applied field parameters. It is commonly accepted that particle core size is a major contributor to signal generation in all the above applications, however, most MNP samples comprise broad distribution spanning nm and more. Therefore, precise knowledge of the exact contribution of individual core sizes to signal generation is desired for optimal MNP design generally for each application. Specifically, we present a magnetic relaxation simulation-driven analysis of experimental frequency mixing magnetic detection (FMMD) for biosensing to quantify the contributions of individual core size fractions towards signal generation. Applying our method to two different experimental MNP systems, we found the most dominant contributions from approx. 20 nm sized particles in the two independent MNP systems. Additional comparison between freely suspended and immobilized MNP also reveals insight in the MNP microstructure, allowing to use FMMD for MNP characterization, as well as to further fine-tune its applicability in biosensing.}, language = {en} } @article{EmonsHuellenkremerSchoening2001, author = {Emons, H. and H{\"u}llenkremer, B. and Sch{\"o}ning, Michael Josef}, title = {Detection of metal ions in aqueous solutions by voltohmmetry}, series = {Fresenius' Journal of Analytical Chemistry. 369 (2001), H. 1}, journal = {Fresenius' Journal of Analytical Chemistry. 369 (2001), H. 1}, isbn = {0937-0633}, pages = {42 -- 46}, year = {2001}, language = {en} } @article{EmonsGlueckSchoening2001, author = {Emons, H. and Gl{\"u}ck, O. and Sch{\"o}ning, Michael Josef}, title = {Voltohmmetry - An alternative detection principle at ultrathin metal electrodes in solution}, series = {Chemical and biological sensors and analytical methods : proceedings of the international symposium / Sensor, Physical Electrochemistry, and Organic and Biological Electrochemistry Divisions. Ed.: M. Butler}, journal = {Chemical and biological sensors and analytical methods : proceedings of the international symposium / Sensor, Physical Electrochemistry, and Organic and Biological Electrochemistry Divisions. Ed.: M. Butler}, publisher = {Electrochemical Society}, address = {Pennington, NJ}, isbn = {1-56677-351-2}, pages = {1 -- 3}, year = {2001}, language = {en} } @article{EmonsGlueckHuellenkremeretal.2001, author = {Emons, H. and Gl{\"u}ck, O. and H{\"u}llenkremer, B. and Sch{\"o}ning, Michael Josef}, title = {Voltohmmetry as an alternative detection method at polycrystalline metal film electrodes}, series = {Electroanalysis. 13 (2001), H. 8-9}, journal = {Electroanalysis. 13 (2001), H. 8-9}, isbn = {1040-0397}, pages = {677 -- 680}, year = {2001}, language = {en} } @article{EmonsBaadeSchoening2000, author = {Emons, H. and Baade, A. and Sch{\"o}ning, Michael Josef}, title = {Voltammetric determination of heavy metals in microvolumes of rain water}, series = {Electroanalysis. 12 (2000), H. 15}, journal = {Electroanalysis. 12 (2000), H. 15}, isbn = {1040-0397}, pages = {1171 -- 1176}, year = {2000}, language = {en} } @article{DollWagnerWagneretal.2016, author = {Doll, Theodor and Wagner, Torsten and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Engineering of functional interfaces / Theodor Doll ; Torsten Wagner ; Patrick Wagner ; Michael J. Sch{\"o}ning (eds.)}, series = {Physica status solidi (a)}, volume = {213}, journal = {Physica status solidi (a)}, number = {6}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.201670641}, pages = {1393 -- 1394}, year = {2016}, language = {en} } @article{DeppeKlatteBongaertsetal.2011, author = {Deppe, Veronika Maria and Klatte, Stephanie and Bongaerts, Johannes and Maurer, Karl-Heinz and O'Connell, Timothy and Meinhardt, Friedhelm}, title = {Genetic control of Amadori product degradation in Bacillus subtilis via regulation of frlBONMD expression by FrlR}, series = {Applied and environmental microbiology}, volume = {Vol. 77}, journal = {Applied and environmental microbiology}, number = {No. 9}, publisher = {American Society of Mechanical Engineers (ASME)}, address = {New York}, issn = {1098-5336 (E-Journal); 0003-6919 (Print); 0099-2240 (Print)}, pages = {2839 -- 2846}, year = {2011}, language = {en} } @article{DeppeBongaertsO'Connelletal.2011, author = {Deppe, Veronika Maria and Bongaerts, Johannes and O'Connell, Timothy and Maurer, Karl-Heinz and Meinhardt, Friedhelm}, title = {Enzymatic deglycation of Amadori products in bacteria}, series = {Applied microbiology and biotechnology}, volume = {Vol. 90}, journal = {Applied microbiology and biotechnology}, number = {Iss. 2}, publisher = {Springer}, address = {Berlin}, issn = {1432-0614 (E-Journal); 0171-1741 (Print); 0175-7598 (Print); 0340-2118 (Print)}, pages = {399 -- 406}, year = {2011}, language = {en} } @article{DelleHuckBaeckeretal.2015, author = {Delle, Lotta E. and Huck, Christina and B{\"a}cker, Matthias and M{\"u}ller, Frank and Grandthyll, Samuel and Jacobs, Karin and Lilischkis, Rainer and Vu, Xuan T. and Sch{\"o}ning, Michael Josef and Wagner, Patrick and Thoelen, Roland and Weil, Maryam and Ingebrandt, Sven}, title = {Impedimetric immunosensor for the detection of histamine based on reduced graphene oxide}, series = {Physica status solidi (a)}, volume = {212}, journal = {Physica status solidi (a)}, number = {6}, publisher = {Wiley}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.201431863}, pages = {1327 -- 1334}, year = {2015}, language = {en} } @article{DegeringEggertPulsetal.2010, author = {Degering, Christian and Eggert, Thorsten and Puls, Michael and Bongaerts, Johannes and Evers, Stefan and Maurer, Karl-Heinz and Jaeger, Karl-Erich}, title = {Optimization of protease secretion in Bacillus subtilis and Bacillus licheniformis by screening of homologous and herologous signal peptides}, series = {Applied and environmental microbiology}, volume = {76}, journal = {Applied and environmental microbiology}, number = {19}, publisher = {American Society for Microbiology}, address = {Washington, DC}, issn = {1098-5336 (E-Journal); 0003-6919 (Print); 0099-2240 (Print)}, doi = {10.1128/AEM.01146-10}, pages = {6370 -- 6378}, year = {2010}, abstract = {Bacillus subtilis and Bacillus licheniformis are widely used for the large-scale industrial production of proteins. These strains can efficiently secrete proteins into the culture medium using the general secretion (Sec) pathway. A characteristic feature of all secreted proteins is their N-terminal signal peptides, which are recognized by the secretion machinery. Here, we have studied the production of an industrially important secreted protease, namely, subtilisin BPN′ from Bacillus amyloliquefaciens. One hundred seventy-three signal peptides originating from B. subtilis and 220 signal peptides from the B. licheniformis type strain were fused to this secretion target and expressed in B. subtilis, and the resulting library was analyzed by high-throughput screening for extracellular proteolytic activity. We have identified a number of signal peptides originating from both organisms which produced significantly increased yield of the secreted protease. Interestingly, we observed that levels of extracellular protease were improved not only in B. subtilis, which was used as the screening host, but also in two different B. licheniformis strains. To date, it is impossible to predict which signal peptide will result in better secretion and thus an improved yield of a given extracellular target protein. Our data show that screening a library consisting of homologous and heterologous signal peptides fused to a target protein can identify more-effective signal peptides, resulting in improved protein export not only in the original screening host but also in different production strains.}, language = {en} } @article{DarmoSchaefferFoersteretal.2000, author = {Darmo, J. and Sch{\"a}ffer, F. and F{\"o}rster, Arnold and Kordos, P.}, title = {Beryllium doped low-temperature-grown MBE GaAs: material for photomixing in the THz frequency range}, series = {ASDAM 2000 : conference proceedings / edited by Jozef Osvald ... [et al.]}, journal = {ASDAM 2000 : conference proceedings / edited by Jozef Osvald ... [et al.]}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {0780359399}, pages = {147 -- 150}, year = {2000}, language = {en} } @article{DantismTakenagaWagneretal.2017, author = {Dantism, Shahriar and Takenaga, Shoko and Wagner, Torsten and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Differential imaging of the metabolism of bacteria and eukaryotic cells based on light-addressable potentiometric sensors}, series = {Electrochimica Acta}, volume = {246}, journal = {Electrochimica Acta}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0013-4686}, doi = {10.1016/j.electacta.2017.05.196}, pages = {234 -- 241}, year = {2017}, abstract = {A light-addressable potentiometric sensor (LAPS) is a field-effect-based potentiometric sensor with an electrolyte/insulator/semiconductor (EIS) structure, which is able to monitor analyte concentrations of (bio-)chemical species in aqueous solutions in a spatially resolved way. Therefore, it is also an appropriate tool to record 2D-chemical images of concentration variations on the sensor surface. In the present work, two differential, LAPS-based measurement principles are introduced to determine the metabolic activity of Escherichia coli (E. coli) K12 and Chinese hamster ovary (CHO) cells as test microorganisms. Hereby, we focus on i) the determination of the extracellular acidification rate (ΔpH/min) after adding glucose solutions to the cell suspensions; and ii) recording the amplitude increase of the photocurrent (Iph) related to the produced acids from E. coli K12 bacteria and CHO cells on the sensor surface by 2D-chemical imaging. For this purpose, 3D-printed multi-chamber structures were developed and mounted on the planar sensor-chip surface to define four independent compartments, enabling differential measurements with varying cell concentrations. The differential concept allows eliminating unwanted drift effects and, with the four-chamber structures, measurements on the different cell concentrations were performed simultaneously, thus reducing also the overall measuring time.}, language = {en} } @article{DantismTakenagaWagneretal.2016, author = {Dantism, Shahriar and Takenaga, Shoko and Wagner, Patrick and Wagner, Torsten and Sch{\"o}ning, Michael Josef}, title = {Determination of the extracellular acidification of Escherichia coli K12 with a multi-​chamber-​based LAPS system}, series = {Physica status solidi (a)}, volume = {213}, journal = {Physica status solidi (a)}, number = {6}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1862-6300}, doi = {10.1002/pssa.201533043}, pages = {1479 -- 1485}, year = {2016}, abstract = {On-line monitoring of the metabolic activity of microorganisms involved in intermediate stages of biogas production plays an important role to avoid undesirable "down times" during the biogas production. In order to control this process, an on-chip differential measuring system based on the light-addressable potentiometric sensor (LAPS) principle combined with a 3D-printed multi-chamber structure has been realized. As a test microorganism, Escherichia coli K12 (E. coli K12) were used for cell-based measurements. Multi-chamber structures were developed to determine the metabolic activity of E. coli K12 in suspension for a different number of cells, responding to the addition of a constant or variable amount of glucose concentrations, enabling differential and simultaneous measurements.}, language = {en} } @article{DantismRoehlenWagneretal.2018, author = {Dantism, Shahriar and R{\"o}hlen, Desiree and Wagner, Torsten and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Optimization of Cell-Based Multi-Chamber LAPS Measurements Utilizing FPGA-Controlled Laser-Diode Modules}, series = {physica status solidi a : applications and materials sciences}, volume = {215}, journal = {physica status solidi a : applications and materials sciences}, number = {15}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.201800058}, pages = {Article number 1800058}, year = {2018}, abstract = {A light-addressable potentiometric sensor (LAPS) is a field-effect-based potentiometric device, which detects concentration changes of an analyte solution on the sensor surface in a spatially resolved way. It uses a light source to generate electron-hole pairs inside the semiconductor, which are separated in the depletion region due to an applied bias voltage across the sensor structure and hence, a surface-potential-dependent photocurrent can be read out. However, depending on the beam angle of the light source, scattering effects can occur, which influence the recorded signal in LAPS-based differential measurements. To solve this problem, a novel illumination unit based on a field programmable gate array (FPGA) consisting of 16 small-sized tunable infrared laser-diode modules (LDMs) is developed. Due to the improved focus of the LDMs with a beam angle of only 2 mrad, undesirable scattering effects are minimized. Escherichia coli (E. coli) K12 bacteria are used as a test microorganism to study the extracellular acidification on the sensor surface. Furthermore, a salt bridge chamber is built up and integrated with the LAPS system enabling multi-chamber differential measurements with a single Ag/AgCl reference electrode.}, language = {en} }