@article{HuckPoghossianBaeckeretal.2015, author = {Huck, Christina and Poghossian, Arshak and B{\"a}cker, Matthias and Reisert, Steffen and Kramer, Friederike and Begoyan, Vardges K. and Buniatyan, Vahe V. and Sch{\"o}ning, Michael Josef}, title = {Multi-parameter sensing using high-k oxide of barium strontium titanate}, 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.201431911}, pages = {1259}, year = {2015}, abstract = {High-k perovskite oxide of barium strontium titanate (BST) represents a very attractive multi-functional transducer material for the development of (bio-)chemical sensors. In this work, a Si-based sensor chip containing Pt interdigitated electrodes covered with a thin BST layer (485 nm) has been developed for multi-parameter chemical sensing. The chip has been applied for the contactless measurement of the electrolyte conductivity, the detection of adsorbed charged macromolecules (positively charged polyelectrolytes of polyethylenimine) and the concentration of hydrogen peroxide (H2O2) vapor. The experimental results of functional testing of individual sensors are presented. The mechanism of the BST sensitivity to charged polyelectrolytes and H2O2 vapor has been proposed and discussed.}, language = {en} } @article{HuckPoghossianBaeckeretal.2014, author = {Huck, Christina and Poghossian, Arshak and B{\"a}cker, Matthias and Chaudhuri, S. and Zander, W. and Schubert, J. and Begoyan, V. K. and Buniatyan, V. V. and Wagner, P. and Sch{\"o}ning, Michael Josef}, title = {Capacitively coupled electrolyte-conductivity sensor based on high-k material of barium strontium titanate}, series = {Sensors and actuators. B: Chemical}, journal = {Sensors and actuators. B: Chemical}, number = {198}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-3077 (E-Journal); 0925-4005 (Print)}, doi = {10.1016/j.snb.2014.02.103}, pages = {102 -- 109}, year = {2014}, language = {en} } @article{HoskensRoerTolstikhinetal.2000, author = {Hoskens, R.C.P. and Roer, T.G. van de and Tolstikhin, V.I. and F{\"o}rster, Arnold}, title = {Hot electron injection laser: vertically integrated transistor-laser structure for high-speed, low-chirp direct modulation}, series = {LEOS 2000 : 2000 IEEE annual meeting conference proceedings; 13th annual meeting; IEEE Lasers and Electro-Optics Society 2000 annual meeting; 13-16 November 2000, The Westin Rio Mar Beach, Rio Grande, Puerto Rico. Vol. 2}, journal = {LEOS 2000 : 2000 IEEE annual meeting conference proceedings; 13th annual meeting; IEEE Lasers and Electro-Optics Society 2000 annual meeting; 13-16 November 2000, The Westin Rio Mar Beach, Rio Grande, Puerto Rico. Vol. 2}, publisher = {IEEE Service Center}, address = {Piscataway, NJ}, isbn = {0-7803-5947-X}, pages = {444 -- 445}, year = {2000}, language = {en} } @article{HoskensTolstikhinFoersteretal.2000, author = {Hoskens, R. C. P. and Tolstikhin, V.I. and F{\"o}rster, Arnold and Roer, T.G. van de}, title = {Vertically integrated transistor-laser structure, take 2}, series = {WOCSDICE 2000, 24th Workshop on Compound Semiconductor Devices and Integrated Circuits held in Europe : May 29 - June 02, 2000, Aegean Sea, Greece.}, journal = {WOCSDICE 2000, 24th Workshop on Compound Semiconductor Devices and Integrated Circuits held in Europe : May 29 - June 02, 2000, Aegean Sea, Greece.}, publisher = {Univ. of Michigan}, address = {Ann Arbor, Mich.}, isbn = {0970311109}, pages = {Getr. Z{\"a}hlung [ca. 200 S.]}, year = {2000}, language = {en} } @article{HonarvarfardGamellaPoghossianetal.2017, author = {Honarvarfard, Elham and Gamella, Maria and Poghossian, Arshak and Sch{\"o}ning, Michael Josef and Katz, Evgeny}, title = {An enzyme-based reversible Controlled NOT (CNOT) logic gate operating on a semiconductor transducer}, series = {Applied Materials Today}, volume = {9}, journal = {Applied Materials Today}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-9407}, doi = {10.1016/j.apmt.2017.08.003}, pages = {266 -- 270}, year = {2017}, abstract = {An enzyme-based biocatalytic system mimicking operation of a logically reversible Controlled NOT (CNOT) gate has been interfaced with semiconductor electronic transducers. Electrolyte-insulator-semiconductor (EIS) structures have been used to transduce chemical changes produced by the enzyme system to an electronically readable capacitive output signal using field-effect features of the EIS device. Two enzymes, urease and esterase, were immobilized on the insulating interface of EIS structure producing local pH changes performing XOR logic operation controlled by various combinations of the input signals represented by urea and ethyl butyrate. Another EIS transducer was functionalized with esterase only, thus performing Identity (ID) logic operation for the ethyl butyrate input. Both semiconductor devices assembled in parallel operated as a logically reversible CNOT gate. The present system, despite its simplicity, demonstrated for the first time logically reversible function of the enzyme system transduced electronically with the semiconductor devices. The biomolecular realization of a CNOT gate interfaced with semiconductors is promising for integration into complex biomolecular networks and future biosensor/biomedical applications.}, language = {en} } @article{HonarvarfardGamellaChannaveerappaetal.2017, author = {Honarvarfard, Elham and Gamella, Maria and Channaveerappa, Devika and Darie, Costel C. and Poghossian, Arshak and Sch{\"o}ning, Michael Josef and Katz, Evgeny}, title = {Electrochemically Stimulated Insulin Release from a Modified Graphene-functionalized Carbon Fiber Electrode}, series = {Electroanalysis}, volume = {29}, journal = {Electroanalysis}, number = {6}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1521-4109}, doi = {10.1002/elan.201700095}, pages = {1543 -- 1553}, year = {2017}, abstract = {A graphene-functionalized carbon fiber electrode was modified with adsorbed polyethylenimine to introduce amino functionalities and then with trigonelline and 4-carboxyphenylboronic acid covalently bound to the amino groups. The trigonelline species containing quarterized pyridine groups produced positive charge on the electrode surface regardless of the pH value, while the phenylboronic acid species were neutral below pH 8 and negatively charged above pH 9 (note that their pKa=8.4). The total charge on the monolayer-modified electrode was positive at the neutral pH and negative at pH > 9. Note that 4-carboxyphenylboronic acid was attached to the electrode surface in molar excess to trigonelline, thus allowing the negative charge to dominate on the electrode surface at basic pH. Negatively charged fluorescent dye-labeled insulin (insulin-FITC) was loaded on the modified electrode surface at pH 7.0 due to its electrostatic attraction to the positively charged interface. The local pH in close vicinity to the electrode surface was increased to ca. 9-10 due to consumption of H+ ions upon electrochemical reduction of oxygen proceeding at the potential of -1.0 V (vs. Ag/AgCl) applied on the modified electrode. The process resulted in recharging of the electrode surface to the negative value due to the formation of the negative charge on the phenylboronic acid groups, thus resulting in the electrostatic repulsion of insulin-FITC and stimulating its release from the electrode surface. The insulin release was characterized by fluorescence spectroscopy (using the FITC-labeled insulin), by electrochemical measurements on an iridium oxide, IrOx, electrode and by mass spectrometry. The graphene-functionalized carbon fiber electrode demonstrated significant advantages in the signal-stimulated insulin release comparing with the carbon fiber electrode without the graphene species.}, language = {en} } @article{HodelOrzatiMarsoetal.2000, author = {Hodel, U. and Orzati, A. and Marso, M. and Homann, O. and Fox, A. and Hart, A. v. d. and F{\"o}rster, Arnold and Kordos, P. and L{\"u}th, H.}, title = {A novel InAlAs/InGaAs layer structure for monolithically integrated photoreceiver}, series = {Conference Proceedings: 2000 International Conference on Indium Phosphide and related materials}, journal = {Conference Proceedings: 2000 International Conference on Indium Phosphide and related materials}, publisher = {IEEE Service Center}, address = {Piscataway, NJ}, isbn = {0-7803-6320-5}, pages = {466 -- 469}, year = {2000}, language = {en} } @article{HennemannKohlReisertetal.2013, author = {Hennemann, J{\"o}rg and Kohl, Claus-Dieter and Reisert, Steffen and Kirchner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Copper oxide nanofibres for detection of hydrogen peroxide vapour at high concentrations}, series = {physica status solidi (a)}, volume = {210}, journal = {physica status solidi (a)}, number = {5}, publisher = {Wiley}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.201200775}, pages = {859 -- 863}, year = {2013}, abstract = {We present a sensor concept based on copper(II)oxide (CuO) nanofibres for the detection of hydrogen peroxide (H2O2) vapour in the percent per volume (\% v/v) range. The fibres were produced by using the electrospinning technique. To avoid water condensation in the pores, the fibres were initially modified by an exposure to H2S to get an enclosed surface. By a thermal treatment at 350 °C the fibres were oxidised back to CuO. Thereby, the visible pores disappear which was verified by SEM analysis. The fibres show a decrease of resistance with increasing H2O2 concentration which is due to the fact that hydrogen peroxide is an oxidising gas and CuO a p-type semiconductor. The sensor shows a change of resistance within the minute range to the exposure until the maximum concentration of 6.9\% v/v H2O2. At operating temperatures below 450 °C the corresponding sensor response to a concentration of 4.1\% v/v increases. The sensor shows a good reproducibility of the signal at different measurements. CuO seems to be a suitable candidate for the detection of H2O2 vapour at high concentrations. Resistance behaviour of the sensor under exposure to H2O2 vapours between 2.3 and 6.9\% v/v at an operating temperature of 450 °C.}, language = {en} } @article{HenkenOosterhuisOehlschlaegeretal.2012, author = {Henken, F. E. and Oosterhuis, K. and {\"O}hlschl{\"a}ger, Peter and Bosch, L. and Hooijberg, E. and Haanen, J. B. A. G. and Steenbergen, R. D. M.}, title = {Preclinical safety evaluation of DNA vaccines encoding modified HPV16 E6 and E7}, series = {Vaccine}, volume = {30}, journal = {Vaccine}, number = {28}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0264-410X}, doi = {10.1016/j.vaccine.2012.04.013}, pages = {4259 -- 4266}, year = {2012}, abstract = {Persistent infection with high-risk human papillomaviruses (hrHPV) can result in the formation of anogenital cancers. As hrHPV proteins E6 and E7 are required for cancer initiation and maintenance, they are ideal targets for immunotherapeutic interventions. Previously, we have described the development of DNA vaccines for the induction of HPV16 E6 and E7 specific T cell immunity. These vaccines consist of 'gene-shuffled' (SH) versions of HPV16 E6 and E7 that were fused to Tetanus Toxin Fragment C domain 1 (TTFC) and were named TTFC-E6SH and TTFC-E7SH. Gene-shuffling was performed to avoid the risk of inducing malignant transformation at the vaccination site. Here, we describe the preclinical safety evaluation of these candidate vaccines by analysis of their transforming capacity in vitro using established murine fibroblasts (NIH 3T3 cells) and primary human foreskin keratinocytes (HFKs). We demonstrate that neither ectopic expression of TTFC-E6SH and TTFC-E7SH alone or in combination enabled NIH 3T3 cells to form colonies in soft agar. In contrast, expression of HPV16 E6WT and E7WT alone or in combination resulted in effective transformation. Similarly, retroviral transduction of HFKs from three independent donors with both TTFC-E6SH and TTFC-E7SH alone or in combination did not show any signs of immortalization. In contrast, the combined expression of E6WT and E7WT induced immortalization in HFKs from all donors. Based on these results we consider it justified to proceed to clinical evaluation of DNA vaccines encoding TTFC-E6SH and TTFC-E7SH in patients with HPV16 associated (pre)malignancies.}, language = {en} } @article{HeineHerrmannSelmeretal.2014, author = {Heine, A. and Herrmann, G. and Selmer, Thorsten and Terwesten, F. and Buckel, W. and Reuter, K.}, title = {High resolution crystal structure of clostridium propionicum β-Alanyl-CoA:Ammonia Lyase, a new member of the "Hot Dog Fold" protein superfamily}, series = {Proteins}, volume = {82}, journal = {Proteins}, number = {9}, publisher = {Wiley-Liss}, address = {New York}, issn = {1097-0134 (E-Journal); 0887-3585 (Print)}, doi = {10.1002/prot.24557}, pages = {2041 -- 2053}, year = {2014}, abstract = {Clostridium propionicum is the only organism known to ferment β-alanine, a constituent of coenzyme A (CoA) and the phosphopantetheinyl prosthetic group of holo-acyl carrier protein. The first step in the fermentation is a CoA-transfer to β-alanine. Subsequently, the resulting β-alanyl-CoA is deaminated by the enzyme β-alanyl-CoA:ammonia lyase (Acl) to reversibly form ammonia and acrylyl-CoA. We have determined the crystal structure of Acl in its apo-form at a resolution of 0.97 {\AA} as well as in complex with CoA at a resolution of 1.59 {\AA}. The structures reveal that the enyzme belongs to a superfamily of proteins exhibiting a so called "hot dog fold" which is characterized by a five-stranded antiparallel β-sheet with a long α-helix packed against it. The functional unit of all "hot dog fold" proteins is a homodimer containing two equivalent substrate binding sites which are established by the dimer interface. In the case of Acl, three functional dimers combine to a homohexamer strongly resembling the homohexamer formed by YciA-like acyl-CoA thioesterases. Here, we propose an enzymatic mechanism based on the crystal structure of the Acl·CoA complex and molecular docking. Proteins 2014; 82:2041-2053. © 2014 Wiley Periodicals, Inc.}, language = {en} } @article{HeiduschkaRomannEckenetal.2001, author = {Heiduschka, P. and Romann, I. and Ecken, H. and Sch{\"o}ning, Michael Josef and Schuhmann, W. and Thanos, S.}, title = {Defined adhesion and growth of neurones on artificial structured substrates}, series = {Scaling down in electrochemistry : electrochemical micro- and nanosystem technology ; proceedings of the 3rd International Symposium on Electrochemical Microsystem Technologies, Garmisch-Patenkirchen, Germany, 11 - 15 September 2000 / ed. by J. W. Schultz}, journal = {Scaling down in electrochemistry : electrochemical micro- and nanosystem technology ; proceedings of the 3rd International Symposium on Electrochemical Microsystem Technologies, Garmisch-Patenkirchen, Germany, 11 - 15 September 2000 / ed. by J. W. Schultz}, publisher = {Elsevier [u.a.]}, address = {Amsterdam [u.a.]}, isbn = {0-08-044014-2}, pages = {299 -- 307}, year = {2001}, language = {en} } @article{HeidenTurekSchoening2011, author = {Heiden, W. and Turek, M. and Sch{\"o}ning, Michael Josef}, title = {TasteIT : Analyzing chemical sensor data using fuzzy logic}, publisher = {IEEE}, address = {New York}, isbn = {978-1-4244-9910-6}, pages = {1 -- 6}, year = {2011}, language = {en} } @article{HeidenTurekSchoening2011, author = {Heiden, W. and Turek, M. and Sch{\"o}ning, Michael Josef}, title = {Analysis of chemical sensor data}, series = {Proceedings of the 4th Russian-German Workshop "Innovation Information Technologies: Theory and practice" : Ufa, Russia, April 8-13, 2011 / eds. Yupsova, Nafisa ...}, journal = {Proceedings of the 4th Russian-German Workshop "Innovation Information Technologies: Theory and practice" : Ufa, Russia, April 8-13, 2011 / eds. Yupsova, Nafisa ...}, publisher = {State Aviation Technical Univ.}, address = {Ufa}, isbn = {978-5-4221-0159-7}, pages = {76 -- 81}, year = {2011}, language = {en} } @article{HandtkeVollandMethlingetal.2014, author = {Handtke, Stefan and Volland, Sonja and Methling, Karen and Albrecht, Dirk and Becher, D{\"o}rte and Nehls, Jenny and Bongaerts, Johannes and Maurer, Karl-Heinz and Lalk, Michael and Liesegang, Heiko and Voigt, Birgit and Daniel, Rolf and Hecker, Michael}, title = {Cell physiology of the biotechnological relevant bacterium Bacillus pumilus - An omics-based approach}, series = {Journal of Biotechnology}, journal = {Journal of Biotechnology}, number = {192(A)}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-4863 (E-Journal); 0168-1656 (Print)}, doi = {10.1016/j.jbiotec.2014.08.028}, pages = {204 -- 214}, year = {2014}, abstract = {Members of the species Bacillus pumilus get more and more in focus of the biotechnological industry as potential new production strains. Based on exoproteome analysis, B. pumilus strain Jo2, possessing a high secretion capability, was chosen for an omics-based investigation. The proteome and metabolome of B. pumilus cells growing either in minimal or complex medium was analyzed. In total, 1542 proteins were identified in growing B. pumilus cells, among them 1182 cytosolic proteins, 297 membrane and lipoproteins and 63 secreted proteins. This accounts for about 43\% of the 3616 proteins encoded in the B. pumilus Jo2 genome sequence. By using GC-MS, IP-LC/MS and H NMR methods numerous metabolites were analyzed and assigned to reconstructed metabolic pathways. In the genome sequence a functional secretion system including the components of the Sec- and Tat-secretion machinery was found. Analysis of the exoproteome revealed secretion of about 70 proteins with predicted secretion signals. In addition, selected production-relevant genome features such as restriction modification systems and NRPS clusters of B. pumilus Jo2 are discussed.}, language = {en} } @article{HamadBilattoAdlyetal.2016, author = {Hamad, E. M. and Bilatto, S. E. R. and Adly, N. Y. and Correa, D. S. and Wolfrum, B. and Sch{\"o}ning, Michael Josef and Offenh{\"a}usser, A. and Yakushenko, A.}, title = {Inkjet printing of UV-curable adhesive and dielectric inks for microfluidic devices}, series = {Lab on a Chip}, volume = {16}, journal = {Lab on a Chip}, number = {1}, publisher = {Royal Society of Chemistry}, address = {Cambridge}, issn = {1473-0189}, doi = {10.1039/C5LC01195G}, pages = {70 -- 74}, year = {2016}, abstract = {Bonding of polymer-based microfluidics to polymer substrates still poses a challenge for Lab-On-a-Chip applications. Especially, when sensing elements are incorporated, patterned deposition of adhesives with curing at ambient conditions is required. Here, we demonstrate a fabrication method for fully printed microfluidic systems with sensing elements using inkjet and stereolithographic 3D-printing.}, language = {en} } @article{HaegerGrankinWagner2023, author = {Haeger, Gerrit and Grankin, Alina and Wagner, Michaela}, title = {Construction of an Aspergillus oryzae triple amylase deletion mutant as a chassis to evaluate industrially relevant amylases using multiplex CRISPR/Cas9 editing technology}, series = {Applied Research}, journal = {Applied Research}, number = {Early View}, publisher = {Wiley-VCH}, issn = {2702-4288}, doi = {10.1002/appl.202200106}, pages = {1 -- 15}, year = {2023}, abstract = {Aspergillus oryzae is an industrially relevant organism for the secretory production of heterologous enzymes, especially amylases. The activities of potential heterologous amylases, however, cannot be quantified directly from the supernatant due to the high background activity of native α-amylase. This activity is caused by the gene products of amyA, amyB, and amyC. In this study, an in vitro CRISPR/Cas9 system was established in A. oryzae to delete these genes simultaneously. First, pyrG of A. oryzae NSAR1 was mutated by exploiting NHEJ to generate a counter-selection marker. Next, all amylase genes were deleted simultaneously by co-transforming a repair template carrying pyrG of Aspergillus nidulans and flanking sequences of amylase gene loci. The rate of obtained triple knock-outs was 47\%. We showed that triple knockouts do not retain any amylase activity in the supernatant. The established in vitro CRISPR/Cas9 system was used to achieve sequence-specific knock-in of target genes. The system was intended to incorporate a single copy of the gene of interest into the desired host for the development of screening methods. Therefore, an integration cassette for the heterologous Fpi amylase was designed to specifically target the amyB locus. The site-specific integration rate of the plasmid was 78\%, with exceptional additional integrations. Integration frequency was assessed via qPCR and directly correlated with heterologous amylase activity. Hence, we could compare the efficiency between two different signal peptides. In summary, we present a strategy to exploit CRISPR/Cas9 for gene mutation, multiplex knock-out, and the targeted knock-in of an expression cassette in A. oryzae. Our system provides straightforward strain engineering and paves the way for development of fungal screening systems.}, language = {en} } @article{HaegerBongaertsSiegert2022, author = {Haeger, Gerrit and Bongaerts, Johannes and Siegert, Petra}, title = {A convenient ninhydrin assay in 96-well format for amino acid-releasing enzymes using an air-stable reagent}, series = {Analytical Biochemistry}, journal = {Analytical Biochemistry}, number = {624}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1096-0309}, doi = {10.1016/j.ab.2022.114819}, pages = {Artikel 114819}, year = {2022}, abstract = {An improved and convenient ninhydrin assay for aminoacylase activity measurements was developed using the commercial EZ Nin™ reagent. Alternative reagents from literature were also evaluated and compared. The addition of DMSO to the reagent enhanced the solubility of Ruhemann's purple (RP). Furthermore, we found that the use of a basic, aqueous buffer enhances stability of RP. An acidic protocol for the quantification of lysine was developed by addition of glacial acetic acid. The assay allows for parallel processing in a 96-well format with measurements microtiter plates.}, language = {en} } @article{GuoSekiMiyamotoetal.2014, author = {Guo, Yuanyuan and Seki, Kosuke and Miyamoto, Ko-ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo}, title = {Novel photoexcitation method for light-addressable potentiometric sensor with higher spatial resolution}, series = {Applied physics express : APEX}, volume = {7}, journal = {Applied physics express : APEX}, number = {6}, publisher = {IOP}, address = {Bristol}, issn = {1882-0786 (E-Journa); 1882-0778 (Print)}, doi = {10.7567/APEX.7.067301}, pages = {067301-4}, year = {2014}, abstract = {A novel photoexcitation method for the light-addressable potentiometric sensor (LAPS) is proposed to achieve a higher spatial resolution of chemical images. The proposed method employs a combined light source that consists of a modulated light probe, which generates the alternating photocurrent signal, and a ring of constant illumination surrounding it. The constant illumination generates a sheath of carriers with increased concentration which suppresses the spread of photocarriers by enhanced recombination. A device simulation was carried out to verify the effect of constant illumination on the spatial resolution, which demonstrated that a higher spatial resolution can be obtained.}, language = {en} } @article{GuoMiyamotoWagneretal.2014, author = {Guo, Yuanyuan and Miyamoto, Ko-ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo}, title = {Theoretical study and simulation of light-addressable potentiometric sensors}, series = {Physica status solidi (A) : applications and materials}, volume = {211}, journal = {Physica status solidi (A) : applications and materials}, number = {6}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0031-8965}, doi = {10.1002/pssa.201330354}, pages = {1467 -- 1472}, year = {2014}, abstract = {The light-addressable potentiometric sensor (LAPS) is a semiconductor-based potentiometric sensor using a light probe with an ability of detecting the concentration of biochemical species in a spatially resolved manner. As an important biomedical sensor, research has been conducted to improve its performance, for instance, to realize high-speed measurement. In this work, the idea of facilitating the device-level simulation, instead of using an equivalent-circuit model, is presented for detailed analysis and optimization of the performance of the LAPS. Both carrier distribution and photocurrent response have been simulated to provide new insight into both amplitude-mode and phase-mode operations of the LAPS. Various device parameters can be examined to effectively design and optimize the LAPS structures and setups for enhanced performance.}, language = {en} } @article{GuoMiyamotoWagneretal.2014, author = {Guo, Yuanyuan and Miyamoto, Ko-ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo}, title = {Device simulation of the light-addressable potentiometric sensor for the investigation of the spatial resolution}, series = {Sensors and actuators B: Chemical}, volume = {204}, journal = {Sensors and actuators B: Chemical}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-3077 (E-Journal); 0925-4005 (Print)}, doi = {10.1016/j.snb.2014.08.016}, pages = {659 -- 665}, year = {2014}, abstract = {As a semiconductor-based electrochemical sensor, the light-addressable potentiometric sensor (LAPS) can realize two dimensional visualization of (bio-)chemical reactions at the sensor surface addressed by localized illumination. Thanks to this imaging capability, various applications in biochemical and biomedical fields are expected, for which the spatial resolution is critically significant. In this study, therefore, the spatial resolution of the LAPS was investigated in detail based on the device simulation. By calculating the spatiotemporal change of the distributions of electrons and holes inside the semiconductor layer in response to a modulated illumination, the photocurrent response as well as the spatial resolution was obtained as a function of various parameters such as the thickness of the Si substrate, the doping concentration, the wavelength and the intensity of illumination. The simulation results verified that both thinning the semiconductor substrate and increasing the doping concentration could improve the spatial resolution, which were in good agreement with known experimental results and theoretical analysis. More importantly, new findings of interests were also obtained. As for the dependence on the wavelength of illumination, it was found that the known dependence was not always the case. When the Si substrate was thick, a longer wavelength resulted in a higher spatial resolution which was known by experiments. When the Si substrate was thin, however, a longer wavelength of light resulted in a lower spatial resolution. This finding was explained as an effect of raised concentration of carriers, which reduced the thickness of the space charge region. The device simulation was found to be helpful to understand the relationship between the spatial resolution and device parameters, to understand the physics behind it, and to optimize the device structure and measurement conditions for realizing higher performance of chemical imaging systems.}, language = {en} } @article{GunSchoeningAbouzaretal.2008, author = {Gun, Jenny and Sch{\"o}ning, Michael Josef and Abouzar, Maryam H. and Poghossian, Arshak and Katz, Evgeny}, title = {Field-Effect Nanoparticle-Based Glucose Sensor on a Chip: Amplification Effect of Coimmobilized Redox Species}, series = {Electroanalysis. 20 (2008), H. 16}, journal = {Electroanalysis. 20 (2008), H. 16}, isbn = {1521-4109}, pages = {1748 -- 1753}, year = {2008}, language = {en} } @article{GunRizkovLevetal.2008, author = {Gun, Jenny and Rizkov, Dan and Lev, Ovadia and Abouzar, Maryam H. and Poghossian, Arshak and Sch{\"o}ning, Michael Josef}, title = {Oxygen plasma-treated gold nanoparticle-based field-effect devices as transducer structures for bio-chemical sensing}, series = {Microchimica Acta. 164 (2008), H. 3-4}, journal = {Microchimica Acta. 164 (2008), H. 3-4}, isbn = {1436-5073}, pages = {395 -- 404}, year = {2008}, language = {en} } @article{GunGutkinLevetal.2011, author = {Gun, Jenny and Gutkin, Vitaly and Lev, Ovadia and Boyen, Hans-Gerd and Saitner, Marc and Wagner, Patrick and Olieslaeger, Marc D´ and Abouzar, Maryam H. and Poghossian, Arshak and Sch{\"o}ning, Michael Josef}, title = {Tracing gold nanoparticle charge by electrolyte-insulator-semiconductor devices}, series = {Journal of Physical Chemistry C. 115 (2011), H. 11}, journal = {Journal of Physical Chemistry C. 115 (2011), H. 11}, publisher = {American Cemical Society}, address = {Washington, DC}, isbn = {1932-7455}, pages = {4439 -- 4445}, year = {2011}, language = {en} } @article{GrinsvenBonStrauvenetal.2012, author = {Grinsven, Bart van and Bon, Natalie vanden and Strauven, Hannelore and Grieten, Lars and Murib, Mohammed and Jim{\´e}nez Monroy, Kathia L. and Janssens, Stoffel D. and Haenen, Ken and Sch{\"o}ning, Michael Josef and Vermeeren, Veronique and Ameloot, Marcel and Michiels, Luc and Thoelen, Ronald and Ceuninck, Ward de and Wagner, Patrick}, title = {Heat-Transfer Resistance at Solid-Liquid Interfaces: A Tool for The Detection of Single Nucleotide Polymorphisms in DNA.}, series = {ACS Nano}, volume = {6}, journal = {ACS Nano}, number = {3}, publisher = {ACS Publications}, address = {Washington, DC}, issn = {1936-086X}, doi = {10.1021/nn300147e}, pages = {2712 -- 2721}, year = {2012}, abstract = {In this article, we report on the heat-transfer resistance at interfaces as a novel, denaturation-based method to detect single-nucleotide polymorphisms in DNA. We observed that a molecular brush of double-stranded DNA grafted onto synthetic diamond surfaces does not notably affect the heat-transfer resistance at the solid-to-liquid interface. In contrast to this, molecular brushes of single-stranded DNA cause, surprisingly, a substantially higher heat-transfer resistance and behave like a thermally insulating layer. This effect can be utilized to identify ds-DNA melting temperatures via the switching from low- to high heat-transfer resistance. The melting temperatures identified with this method for different DNA duplexes (29 base pairs without and with built-in mutations) correlate nicely with data calculated by modeling. The method is fast, label-free (without the need for fluorescent or radioactive markers), allows for repetitive measurements, and can also be extended toward array formats. Reference measurements by confocal fluorescence microscopy and impedance spectroscopy confirm that the switching of heat-transfer resistance upon denaturation is indeed related to the thermal on-chip denaturation of DNA.}, language = {en} } @article{GrinsvenBonGrietenetal.2011, author = {Grinsven, B. van and Bon, N. vanden and Grieten, L. and Murib, M. and Janssen, S. D. and Haenen, K. and Schneider, E. and Ingebrandt, E. and Sch{\"o}ning, Michael Josef and Vermeeren, V. and Ameloot, M. and Michiels, L. and Thoelen, R. and Ceuninck, W. de and Wagner, P.}, title = {Rapid assessment of the stability of DNA duplexes by impedimetric real-time monitoring of chemically induced denaturation}, series = {Lab on a Chip}, volume = {11}, journal = {Lab on a Chip}, number = {9}, publisher = {Royal Society of Chemistry (RSC)}, address = {Cambridge}, isbn = {1473-0197}, pages = {1656 -- 1663}, year = {2011}, language = {en} } @article{GivanoudiCornelisRasschaertetal.2021, author = {Givanoudi, Stella and Cornelis, Peter and Rasschaert, Geertrui and Wackers, Gideon and Iken, Heiko and Rolka, David and Yongabi, Derick and Robbens, Johan and Sch{\"o}ning, Michael Josef and Heyndrickx, Marc and Wagner, Patrick}, title = {Selective Campylobacter detection and quantification in poultry: A sensor tool for detecting the cause of a common zoonosis at its source}, series = {Sensors and Actuators B: Chemical}, journal = {Sensors and Actuators B: Chemical}, number = {In Press, Journal Pre-proof}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0925-4005}, doi = {10.1016/j.snb.2021.129484}, pages = {Article 129484}, year = {2021}, language = {en} } @article{GeMeyerSchoeningetal.2000, author = {Ge, B. and Meyer, T. and Sch{\"o}ning, Michael Josef and Wollenberger, U. and Lisdat, F.,}, title = {Cytochrome c' from Chromatium vinosum on gold electrodes}, series = {Electrochemistry Communications. 2 (2000), H. 8}, journal = {Electrochemistry Communications. 2 (2000), H. 8}, isbn = {1388-2481}, pages = {557 -- 561}, year = {2000}, language = {en} } @article{GasparyanPoghossianVitusevichetal.2011, author = {Gasparyan, Ferdinand V. and Poghossian, Arshak and Vitusevich, Svetlana A. and Petrychuk, Mykhaylo V. and Sydoruk, Viktor A. and Siqueira, Jos{\´e} R. Jr. and Oliveira, Osvaldo N. Jr. and Offenh{\"a}usser, Andreas and Sch{\"o}ning, Michael Josef}, title = {Low-Frequency Noise in Field-Effect Devices Functionalized With Dendrimer/Carbon-Nanotube Multilayers}, series = {IEEE Sensors Journal. 11 (2011), H. 1}, journal = {IEEE Sensors Journal. 11 (2011), H. 1}, publisher = {IEEE}, address = {New York}, isbn = {1530-437X}, pages = {142 -- 149}, year = {2011}, language = {en} } @article{GasparyanVitusevichOffenhaeusseretal.2011, author = {Gasparyan, F.V. and Vitusevich, S.A. and Offenh{\"a}usser, A. and Sch{\"o}ning, Michael Josef}, title = {Modified charge fluctuation noise model for electrolyte-insulator-semiconductor devices}, series = {Modern Physics Letters B (MPLB). 25 (2011), H. 11}, journal = {Modern Physics Letters B (MPLB). 25 (2011), H. 11}, publisher = {World Scientific Publ.}, address = {Singapur}, isbn = {0217-9849}, pages = {831 -- 840}, year = {2011}, language = {en} } @article{GasparyanPoghossianVitusevichetal.2009, author = {Gasparyan, F. V. and Poghossian, Arshak and Vitusevich, S. A. and Petrychuk, M. V. and Sydoruk, V. A. and Surmalyan, A. V. and Siqueira, J. R. and Oliveira, O. N. and Offenh{\"a}usser, A. and Sch{\"o}ning, Michael Josef}, title = {Low Frequency Noise In Electrolyte-Gate Field-Effect Devices Functionalized With Dendrimer/Carbon-Nanotube Multilayers}, series = {Noise and fluctuations : 20th International Conference on Noise and Fluctuations, ICNF 2009, Pisa, Italy, 14 - 19 June 2009 / ed. Massimo Macucci; Giovanni Basso}, journal = {Noise and fluctuations : 20th International Conference on Noise and Fluctuations, ICNF 2009, Pisa, Italy, 14 - 19 June 2009 / ed. Massimo Macucci; Giovanni Basso}, publisher = {American Inst. of Physics}, address = {Melville, NY}, isbn = {9780735406650}, pages = {133 -- 136}, year = {2009}, language = {en} } @article{GamellaZakharchenkoGuzetal.2017, author = {Gamella, Maria and Zakharchenko, Andrey and Guz, Nataliia and Masi, Madeline and Minko, Sergiy and Kolpashchikov, Dmitry M. and Iken, Heiko and Poghossian, Arshak and Sch{\"o}ning, Michael Josef and Katz, Evgeny}, title = {DNA computing system activated by electrochemically triggered DNA realease from a polymer-brush-modified electrode array}, series = {Electroanalysis}, volume = {29}, journal = {Electroanalysis}, number = {2}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1521-4109}, doi = {10.1002/elan.201600389}, pages = {398 -- 408}, year = {2017}, abstract = {An array of four independently wired indium tin oxide (ITO) electrodes was used for electrochemically stimulated DNA release and activation of DNA-based Identity, AND and XOR logic gates. Single-stranded DNA molecules were loaded on the mixed poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA)/poly(methacrylic acid) (PMAA) brush covalently attached to the ITO electrodes. The DNA deposition was performed at pH 5.0 when the polymer brush is positively charged due to protonation of tertiary amino groups in PDMAEMA, thus resulting in electrostatic attraction of the negatively charged DNA. By applying electrolysis at -1.0 V(vs. Ag/AgCl reference) electrochemical oxygen reduction resulted in the consumption of hydrogen ions and local pH increase near the electrode surface. The process resulted in recharging the polymer brush to the negative state due to dissociation of carboxylic groups of PMAA, thus repulsing the negatively charged DNA and releasing it from the electrode surface. The DNA release was performed in various combinations from different electrodes in the array assembly. The released DNA operated as input signals for activation of the Boolean logic gates. The developed system represents a step forward in DNA computing, combining for the first time DNA chemical processes with electronic input signals.}, language = {en} } @article{FoersterStockIndlekofer2002, author = {F{\"o}rster, Arnold and Stock, J. and Indlekofer, K. M.}, title = {Perspectives of resonant tunneling diodes}, series = {Recent research developments in materials science \& engineering/ 1,2}, journal = {Recent research developments in materials science \& engineering/ 1,2}, publisher = {Transworld Research Network}, address = {Trivandrum, India}, isbn = {81-7895-057-X}, pages = {527 -- 556}, year = {2002}, language = {en} } @article{FoersterLepsaFreundt2007, author = {F{\"o}rster, Arnold and Lepsa, M. I. and Freundt, D.}, title = {Hot electron injector Gunn diode for advanced driver assistance systems}, series = {Applied physics A: materials science and processing. 87 (2007), H. 3}, journal = {Applied physics A: materials science and processing. 87 (2007), H. 3}, isbn = {0947-8396}, pages = {545 -- 558}, year = {2007}, language = {en} } @article{Foerster2000, author = {F{\"o}rster, Arnold}, title = {Resonant tunneling diodes operating as modern quantum transport devices}, series = {Proceedings of the Tenth International Workshop on the Physics of Semiconductor Devices : (December 14 - 18, 1999) / ed.: Vikram Kumar ... - Vol. 2}, journal = {Proceedings of the Tenth International Workshop on the Physics of Semiconductor Devices : (December 14 - 18, 1999) / ed.: Vikram Kumar ... - Vol. 2}, publisher = {Allied Publ.}, address = {New Delhi [u.a.]}, isbn = {81-7023-998-2}, pages = {966 -- 966}, year = {2000}, language = {en} } @article{FuruichiYoshinobuErmelenkoetal.2001, author = {Furuichi, K. and Yoshinobu, T. and Ermelenko, T. and Mourzina, Y. and Iwasaki, H. and Sch{\"o}ning, Michael Josef}, title = {Simultaneous visualization of multiple ions by the chemical imaging sensor}, 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 = {399 -- 401}, year = {2001}, language = {en} } @article{FigueroaMirandaFengShiuetal.2018, author = {Figueroa-Miranda, Gabriela and Feng, Lingyan and Shiu, Simon Chi-Chin and Dirkzwager, Roderick Marshall and Cheung, Yee-Wai and Tanner, Julian Alexander and Sch{\"o}ning, Michael Josef and Offenh{\"a}usser, Andreas and Mayer, Dirk}, title = {Aptamer-based electrochemical biosensor for highly sensitive and selective malaria detection with adjustable dynamic response range and reusability}, series = {Sensor and Actuators B: Chemical}, volume = {255}, journal = {Sensor and Actuators B: Chemical}, number = {P1}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0925-4005}, doi = {10.1016/j.snb.2017.07.117}, pages = {235 -- 243}, year = {2018}, abstract = {Malaria infection remains a significant risk for much of the population of tropical and subtropical areas, particularly in developing countries. Therefore, it is of high importance to develop sensitive, accurate and inexpensive malaria diagnosis tests. Here, we present a novel aptamer-based electrochemical biosensor (aptasensor) for malaria detection by impedance spectroscopy, through the specific recognition between a highly discriminatory DNA aptamer and its target Plasmodium falciparum lactate dehydrogenase (PfLDH). Interestingly, due to the isoelectric point (pI) of PfLDH, the aptasensor response showed an adjustable detection range based on the different protein net-charge at variable pH environments. The specific aptamer recognition allows sensitive protein detection with an expanded detection range and a low detection limit, as well as a high specificity for PfLDH compared to analogous proteins. The specific feasibility of the aptasensor is further demonstrated by detection of the target PfLDH in human serum. Furthermore, the aptasensor can be easily regenerated and thus applied for multiple usages. The robustness, sensitivity, and reusability of the presented aptasensor make it a promising candidate for point-of-care diagnostic systems.}, language = {en} } @article{FassbenderSchmittSchoeningetal.2000, author = {Faßbender, F. and Schmitt, G. and Sch{\"o}ning, Michael Josef and L{\"u}th, H. and Buß, G. and Schultze, J. W.}, title = {Optimization of passivation layers for corrosion protection of silicon-based microelectrode arrays}, series = {Sensors and Actuators B. 68 (2000), H. 1-3}, journal = {Sensors and Actuators B. 68 (2000), H. 1-3}, isbn = {0925-4005}, pages = {128 -- 133}, year = {2000}, language = {en} } @article{FalkenbergBottBongaertsetal.2022, author = {Falkenberg, Fabian and Bott, Michael and Bongaerts, Johannes and Siegert, Petra}, title = {Phylogenetic survey of the subtilase family and a data-mining-based search for new subtilisins from Bacillaceae}, series = {Frontiers in Microbiology}, volume = {2022}, journal = {Frontiers in Microbiology}, number = {13}, publisher = {Frontiers}, address = {Lausanne}, issn = {1664-302X}, doi = {10.3389/fmicb.2022.1017978}, pages = {Artikel 13:1017978}, year = {2022}, abstract = {The subtilase family (S8), a member of the clan SB of serine proteases are ubiquitous in all kingdoms of life and fulfil different physiological functions. Subtilases are divided in several groups and especially subtilisins are of interest as they are used in various industrial sectors. Therefore, we searched for new subtilisin sequences of the family Bacillaceae using a data mining approach. The obtained 1,400 sequences were phylogenetically classified in the context of the subtilase family. This required an updated comprehensive overview of the different groups within this family. To fill this gap, we conducted a phylogenetic survey of the S8 family with characterised holotypes derived from the MEROPS database. The analysis revealed the presence of eight previously uncharacterised groups and 13 subgroups within the S8 family. The sequences that emerged from the data mining with the set filter parameters were mainly assigned to the subtilisin subgroups of true subtilisins, high-alkaline subtilisins, and phylogenetically intermediate subtilisins and represent an excellent source for new subtilisin candidates.}, language = {en} } @article{ErmolenkoVlasovKolodnikovetal.2004, author = {Ermolenko, Y.E. and Vlasov, Y.G. and Kolodnikov, V.V. and Shabaldkin, D. A. and Kloock, Joachim P. and Sch{\"o}ning, Michael Josef}, title = {Diffusion of radioactive tracers (204Tl, 110mAg) and ionic conductivity in membrane materials for the chemical sensors}, series = {Advances in nuclear and radiochemistry : extended abstracts of papers presented at the Sixth International Conference on Nuclear and Radiochemistry (NRC-6), 29 August to 3 September 2004, Aachen, Germany ; in cooperation with University of Cologne, GDCh, FECS, OECD-NEA and IAEA / Syed M. Qaim ... (eds.).}, journal = {Advances in nuclear and radiochemistry : extended abstracts of papers presented at the Sixth International Conference on Nuclear and Radiochemistry (NRC-6), 29 August to 3 September 2004, Aachen, Germany ; in cooperation with University of Cologne, GDCh, FECS, OECD-NEA and IAEA / Syed M. Qaim ... (eds.).}, publisher = {Forschungszentrum J{\"u}lich, Zentralbibliothek}, address = {J{\"u}lich}, isbn = {3893363629}, pages = {483 -- 485}, year = {2004}, language = {en} } @article{ErmolenkoYoshinobuMourzinaetal.2004, author = {Ermolenko, Y. E. and Yoshinobu, T. and Mourzina, Y. G. and Vlasov, Y. G. and Sch{\"o}ning, Michael Josef and Iwasaki, H.}, title = {Laserscanned transducer (LSST) as a multisensor system}, series = {Sensors and Actuators B. 103 (2004), H. 1-2}, journal = {Sensors and Actuators B. 103 (2004), H. 1-2}, isbn = {0925-4005}, pages = {457 -- 462}, year = {2004}, language = {en} } @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} }