TY  - JOUR
A1  - Schusser, Sebastian
A1  - Poghossian, Arshak
A1  - Bäcker, Matthias
A1  - Krischer, M.
A1  - Leinhos, Marcel
A1  - Wagner, P.
A1  - Schöning, Michael Josef
T1  - An application of field-effect sensors for in-situ monitoring of degradation of biopolymers
JF  - Sensors and actuators B: Chemical
N2  - The characterization of the degradation kinetics of biodegradable polymers is mandatory with regard to their proper application. In the present work, polymer-modified electrolyte–insulator–semiconductor (PMEIS) field-effect sensors have been applied for in-situ monitoring of the pH-dependent degradation kinetics of the commercially available biopolymer poly(d,l-lactic acid) (PDLLA) in buffer solutions from pH 3 to pH 13. PDLLA films of 500 nm thickness were deposited on the surface of an Al–p-Si–SiO2–Ta2O5 structure from a polymer solution by means of spin-coating method. The PMEIS sensor is, in principle, capable to detect any changes in bulk, surface and interface properties of the polymer induced by degradation processes. A faster degradation has been observed for PDLLA films exposed to alkaline solutions (pH 9, pH 11 and pH 13).
Y1  - 2015
U6  - https://doi.org/10.1016/j.snb.2014.10.058
SN  - 1873-3077 (E-Journal); 0925-4005 (Print)
VL  - 207, Part B
SP  - 954
EP  - 959
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Schusser, Sebastian
A1  - Krischer, M.
A1  - Molin, D. G. M.
A1  - Akker, N. M. S. van den
A1  - Bäcker, Matthias
A1  - Poghossian, Arshak
A1  - Schöning, Michael Josef
T1  - Sensor System for in-situ and Real-time Monitoring of Polymer (bio) degradation
JF  - Procedia Engineering
N2  - A sensor system for investigating (bio)degradationprocesses of polymers is presented. The system utilizes semiconductor field-effect sensors and is capable of monitoring the degradation process in-situ and in real-time. The degradation of the polymer poly(d,l-lactic acid) is exemplarily monitored in solutions with different pH value, pH-buffer solution containing the model enzyme lipase from Rhizomucormiehei and cell-culture medium containing supernatants from stimulated and non-stimulated THP-1-derived macrophages mimicking activation of the immune system.
Y1  - 2015
U6  - https://doi.org/10.1016/j.proeng.2015.08.815
SN  - 1877-7058
N1  - Eurosensors 2015
VL  - 120
SP  - 948
EP  - 951
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Duong, Minh Tuan
A1  - Nguyen, Nhu Huynh
A1  - Tran, Thanh Ngoc
A1  - Tolba, R. H.
A1  - Staat, Manfred
T1  - Influence of refrigerated storage on tensile mechanical properties of porcine liver and spleen
JF  - International biomechanics
Y1  - 2015
U6  - https://doi.org/10.1080/23335432.2015.1049295
SN  - 2333-5432
VL  - Vol. 2
IS  - Iss. 1
SP  - 79
EP  - 88
PB  - Taylor & Francis
CY  - London
ER  - 
TY  - JOUR
A1  - Bronder, Thomas
A1  - Poghossian, Arshak
A1  - Scheja, Sabrina
A1  - Wu, Chunsheng
A1  - Keusgen, Michael
A1  - Mewes, Dieter
A1  - Schöning, Michael Josef
T1  - DNA Immobilization and Hybridization Detection by the Intrinsic Molecular Charge Using Capacitive Field-Effect Sensors Modified with a Charged Weak Polyelectrolyte Layer
JF  - Applied Materials & Interfaces
N2  - Miniaturized setup, compatibility with advanced micro- and nanotechnologies, and ability to detect biomolecules by their intrinsic molecular charge favor the semiconductor field-effect platform as one of the most attractive approaches for the development of label-free DNA chips. In this work, a capacitive field-effect EIS (electrolyte–insulator–semiconductor) sensor covered with a layer-by-layer prepared, positively charged weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)) was used for the label-free electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization. The negatively charged probe single-stranded DNA (ssDNA) molecules were electrostatically adsorbed onto the positively charged PAH layer, resulting in a preferentially flat orientation of the ssDNA molecules within the Debye length, thus yielding a reduced charge-screening effect and a higher sensor signal. Each sensor-surface modification step (PAH adsorption, probe ssDNA immobilization, hybridization with complementary target DNA (cDNA), reducing an unspecific adsorption by a blocking agent, incubation with noncomplementary DNA (ncDNA) solution) was monitored by means of capacitance–voltage and constant-capacitance measurements. In addition, the surface morphology of the PAH layer was studied by atomic force microscopy and contact-angle measurements. High hybridization signals of 34 and 43 mV were recorded in low-ionic strength solutions of 10 and 1 mM, respectively. In contrast, a small signal of 4 mV was recorded in the case of unspecific adsorption of fully mismatched ncDNA. The density of probe ssDNA and dsDNA molecules as well as the hybridization efficiency was estimated using the experimentally measured DNA immobilization and hybridization signals and a simplified double-layer capacitor model. The results of field-effect experiments were supported by fluorescence measurements, verifying the DNA-immobilization and hybridization event.
Y1  - 2015
U6  - https://doi.org/10.1021/acsami.5b05146
VL  - 36
IS  - 7
SP  - 20068
EP  - 20075
PB  - American Chemical Society
CY  - Washington, DC
ER  - 
TY  - JOUR
A1  - Wu, Chunsheng
A1  - Bronder, Thomas
A1  - Poghossian, Arshak
A1  - Werner, Frederik
A1  - Schöning, Michael Josef
T1  - Label-free detection of DNA using light-addressable potentiometric sensor modified with a positively charged polyelectrolyte layer
JF  - Nanoscale
N2  - A multi-spot (16 spots) light-addressable potentiometric sensor (MLAPS) consisting of an Al–p-Si–SiO2 structure modified with a weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)) was applied for the label-free electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization by the intrinsic molecular charge for the first time. To achieve a preferentially flat orientation of DNA strands and thus, to reduce the distance between the DNA charge and MLAPS surface, the negatively charged probe single-stranded DNAs (ssDNA) were electrostatically adsorbed onto the positively charged PAH layer using a simple layer-by-layer (LbL) technique. In this way, more DNA charge can be positioned within the Debye length, yielding a higher sensor signal. The surface potential changes in each spot induced due to the surface modification steps (PAH adsorption, probe ssDNA immobilization, hybridization with complementary target DNA (cDNA), non-specific adsorption of mismatched ssDNA) were determined from the shifts of photocurrent–voltage curves along the voltage axis. A high sensor signal of 83 mV was registered after immobilization of probe ssDNA onto the PAH layer. The hybridization signal increases from 5 mV to 32 mV with increasing the concentration of cDNA from 0.1 nM to 5 μM. In contrast, a small signal of 5 mV was recorded in the case of non-specific adsorption of fully mismatched ssDNA (5 μM). The obtained results demonstrate the potential of the MLAPS in combination with the simple and rapid LbL immobilization technique as a promising platform for the future development of multi-spot light-addressable label-free DNA chips with direct electrical readout.
Y1  - 2015
U6  - https://doi.org/10.1039/C4NR07225A
VL  - 14
IS  - 7
SP  - 6143
EP  - 6150
PB  - Royal Society of Chemistry (RSC)
CY  - Cambridge
ER  - 
TY  - CHAP
A1  - Frotscher, Ralf
A1  - Staat, Manfred
ED  - Nithiarasu, Perumal
T1  - Homogenization of a cardiac tissue construct
T2  - CMBE15 : 4th International Conference on Computational & Mathematical Biomedical Engineering ; 29th June - 1st July 2015 ; École Normale Supérieure de Cachan ; Cachan (Paris), France
Y1  - 2015
SN  - 2227-9385
N1  - Konferenzband unter:
http://www.compbiomed.net/getfile.php?type=12/site_documents&id=Proceedings_2227-9385_compressed.pdf
SP  - 645
EP  - 648
PB  - CMBE
CY  - [s.l.]
ER  - 
TY  - JOUR
A1  - Duong, Minh Tuan
A1  - Nguyen, Nhu Huynh
A1  - Staat, Manfred
T1  - Physical response of hyperelastic models for composite materials and soft tissues
JF  - Asia pacific journal on computational engineering
Y1  - 2015
U6  - https://doi.org/10.1186/s40540-015-0015-x
SN  - 2196-1166
VL  - 2
IS  - 3 (December 2015)
SP  - 1
EP  - 18
ER  - 
TY  - JOUR
A1  - Molinnus, Denise
A1  - Bäcker, Matthias
A1  - Siegert, Petra
A1  - Willenberg, H.
A1  - Poghossian, Arshak
A1  - Keusgen, M.
A1  - Schöning, Michael Josef
T1  - Detection of Adrenaline Based on Substrate Recycling Amplification
JF  - Procedia Engineering
N2  - An amperometric enzyme biosensor has been applied for the detection of adrenaline. The adrenaline biosensor has been prepared by modification of an oxygen electrode with the enzyme laccase that operates at a broad pH range between pH 3.5 to pH 8. The enzyme molecules were immobilized via cross-linking with glutaraldehyde. The sensitivity of the developed adrenaline biosensor in different pH buffer solutions has been studied.
Y1  - 2015
U6  - https://doi.org/10.1016/j.proeng.2015.08.708
SN  - 1877-7058
N1  - Eurosensors 2015
VL  - 120
SP  - 540
EP  - 543
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - CHAP
A1  - Poghossian, Arshak
A1  - Schusser, Sebastian
A1  - Bäcker, M.
A1  - Leinhos, Marcel
A1  - Schöning, Michael Josef
T1  - Real-time in-situ electrical monitoring of the degradation of biopolymers using semiconductor field-effect devices
T2  - Biodegradable biopolymers. Vol. 1
Y1  - 2015
SN  - 978-1-63483-632-6
SP  - 135
EP  - 153
PB  - Nova Science Publ.
CY  - Hauppauge
ER  - 
TY  - CHAP
A1  - Poghossian, Arshak
A1  - Bronder, Thomas
A1  - Wu, Chunsheng
A1  - Schöning, Michael Josef
T1  - Label-free sensing of biomolecules by their intrinsic molecular charge using field-effect devices
T2  - Semiconductor Micro- and Nanoelectonics : Proceedings of the tenth international conference, Yerevan, Armenia, September 11-13
Y1  - 2015
SN  - 978-5-8084-1991-9
SP  - 61
EP  - 63
ER  - 
TY  - JOUR
A1  - Schusser, Sebastian
A1  - Krischer, Maximillian
A1  - Bäcker, Matthias
A1  - Poghossian, Arshak
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Monitoring of the Enzymatically Catalyzed Degradation of Biodegradable Polymers by Means of Capacitive Field-Effect Sensors
JF  - Analytical Chemistry
N2  - Designing novel or optimizing existing biodegradable polymers for biomedical applications requires numerous tests on the effect of substances on the degradation process. In the present work, polymer-modified electrolyte–insulator–semiconductor (PMEIS) sensors have been applied for monitoring an enzymatically catalyzed degradation of polymers for the first time. The thin films of biodegradable polymer poly(d,l-lactic acid) and enzyme lipase were used as a model system. During degradation, the sensors were read-out by means of impedance spectroscopy. In order to interpret the data obtained from impedance measurements, an electrical equivalent circuit model was developed. In addition, morphological investigations of the polymer surface have been performed by means of in situ atomic force microscopy. The sensor signal change, which reflects the progress of degradation, indicates an accelerated degradation in the presence of the enzyme compared to hydrolysis in neutral pH buffer media. The degradation rate increases with increasing enzyme concentration. The obtained results demonstrate the potential of PMEIS sensors as a very promising tool for in situ and real-time monitoring of degradation of polymers.
Y1  - 2015
U6  - https://doi.org/10.1021/acs.analchem.5b00617
SN  - 1520-6882
VL  - 87
IS  - 13
SP  - 6607
EP  - 6613
PB  - ACS Publications
CY  - Washington, DC
ER  - 
TY  - JOUR
A1  - Beging, Stefan
A1  - Leinhos, Marcel
A1  - Jablonski, Melanie
A1  - Poghossian, Arshak
A1  - Schöning, Michael Josef
T1  - Studying the spatially resolved immobilisation of enzymes on a capacitive field-effect structure by means of nano-spotting
JF  - Physica status solidi (a)
Y1  - 2015
U6  - https://doi.org/10.1002/pssa.201431891
SN  - 1862-6319
VL  - 212
IS  - 6
SP  - 1353
EP  - 1358
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Huck, Christina
A1  - Poghossian, Arshak
A1  - Bäcker, Matthias
A1  - Reisert, Steffen
A1  - Kramer, Friederike
A1  - Begoyan, Vardges K.
A1  - Buniatyan, Vahe V.
A1  - Schöning, Michael Josef
T1  - Multi-parameter sensing using high-k oxide of barium strontium titanate
JF  - Physica status solidi (a)
N2  - 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.
Y1  - 2015
U6  - https://doi.org/10.1002/pssa.201431911
SN  - 1862-6319
VL  - 212
IS  - 6
SP  - 1259
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Mulhern, Colm
A1  - Bialonski, Stephan
A1  - Kantz, Holger
T1  - Extreme events due to localization of energy
JF  - Physical Review E
Y1  - 2015
U6  - https://doi.org/10.1103/PhysRevE.91.012918
SN  - 2470-0053
VL  - 91
IS  - 1
SP  - 012918
ER  - 
TY  - JOUR
A1  - Bialonski, Stephan
A1  - Ansmann, Gerrit
A1  - Kantz, Holger
T1  - Data-driven prediction and prevention of extreme events in a spatially extended excitable system
JF  - Physical Review E
Y1  - 2015
U6  - https://doi.org/10.1103/PhysRevE.92.042910
SN  - 2470-0053
VL  - 92
IS  - 4
SP  - 042910
ER  - 
TY  - JOUR
A1  - Baringhaus, Ludwig
A1  - Gaigall, Daniel
T1  - On an independence test approach to the goodness-of-fit problem
JF  - Journal of Multivariate Analysis
N2  - Let X₁,…,Xₙ be independent and identically distributed random variables with distribution F. Assuming that there are measurable functions f:R²→R and g:R²→R characterizing a family F of distributions on the Borel sets of R in the way that the random variables f(X₁,X₂),g(X₁,X₂) are independent, if and only if F∈F, we propose to treat the testing problem H:F∈F,K:F∉F by applying a consistent nonparametric independence test to the bivariate sample variables (f(Xᵢ,Xⱼ),g(Xᵢ,Xⱼ)),1⩽i,j⩽n,i≠j. A parametric bootstrap procedure needed to get critical values is shown to work. The consistency of the test is discussed. The power performance of the procedure is compared with that of the classical tests of Kolmogorov–Smirnov and Cramér–von Mises in the special cases where F is the family of gamma distributions or the family of inverse Gaussian distributions.
KW  - Goodness-of-fit test
KW  - Independence test
KW  - Parametric bootstrap
KW  - Vapnik–Čhervonenkis class
KW  - Gamma distribution
Y1  - 2015
U6  - https://doi.org/10.1016/j.jmva.2015.05.013
SN  - 0047-259X
VL  - 2015
IS  - 140
SP  - 193
EP  - 208
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - CHAP
A1  - Kremers, Alexander
A1  - Pieper, Martin
T1  - Simulation and Verification of Bionic Heat Exchangers with COMSOL Multiphysics® Software
T2  - COMSOL Conference 2015 User Presentations ; COMSOL Conference 2015 Grenoble October 14 - 16, 2015 - World Trade Center, Grenoble, France
Y1  - 2015
PB  - COMSOL
CY  - Göttingen ; Berlin
ER  - 
TY  - JOUR
A1  - Arreola, Julio
A1  - Mätzkow, Malte
A1  - Durán, Marlena Palomar
A1  - Greeff, Anton
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Optimization of the immobilization of bacterial spores on glass substrates with organosilanes
JF  - Physica status solidi (A) : Applications and materials science
N2  - Spores can be immobilized on biosensors to function as sensitive recognition elements. However, the immobilization can affect the sensitivity and reproducibility of the sensor signal. In this work, three different immobilization strategies with organosilanes were optimized and characterized to immobilize Bacillus atrophaeus spores on glass substrates. Five different silanization parameters were investigated: nature of the solvent, concentration of the silane, silanization time, curing process, and silanization temperature. The resulting silane layers were resistant to a buffer solution (e.g., Ringer solution) with a polysorbate (e.g., Tween®80) and sonication.
KW  - silanization
KW  - organosilanes
KW  - immobilization
KW  - endospores
KW  - biosensors
KW  - Bacillus atrophaeus
Y1  - 2016
U6  - https://doi.org/10.1002/pssa.201532914
SN  - 1862-6319
VL  - 213
IS  - 6
SP  - 1463
EP  - 1470
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Murib, M. S.
A1  - Yeap, W. S.
A1  - Eurlings, Y.
A1  - Grinsven, B. van
A1  - Boyen, H.-G.
A1  - Conings, B.
A1  - Michiels, L.
A1  - Ameloot, M.
A1  - Carleer, R.
A1  - Warmer, J.
A1  - Kaul, P.
A1  - Haenen, K.
A1  - Schöning, Michael Josef
A1  - Ceuninck, W. de
A1  - Wagner, P.
T1  - Heat-transfer based characterization of DNA on synthetic sapphire chips
JF  - Sensors and Actuators B: Chemical
N2  - In this study, we show that synthetic sapphire (Al₂O₃), an established implant material, can also serve as a platform material for biosensors comparable to nanocrystalline diamond. Sapphire chips, beads, and powder were first modified with (3-aminopropyl) triethoxysilane (APTES), followed by succinic anhydride (SA), and finally single-stranded probe DNA was EDC coupled to the functionalized layer. The presence of the APTES-SA layer on sapphire powders was confirmed by thermogravimetric analyis and Fourier-transform infrared spectroscopy. Using planar sapphire chips as substrates and X-ray photoelectron spectroscopy (XPS) as surface-sensitive tool, the sequence of individual layers was analyzed with respect to their chemical state, enabling the quantification of areal densities of the involved molecular units. Fluorescence microscopy was used to demonstrate the hybridization of fluorescently tagged target DNA to the probe DNA, including denaturation- and re-hybridization experiments. Due to its high thermal conductivity, synthetic sapphire is especially suitable as a chip material for the heat-transfer method, which was employed to distinguish complementary- and non-complementary DNA duplexes containing single-nucleotide polymorphisms. These results indicate that it is possible to detect mutations electronically with a chemically resilient and electrically insulating chip material.
Y1  - 2016
U6  - https://doi.org/10.1016/j.snb.2016.02.027
SN  - 0925-4005
VL  - 230
IS  - 230
SP  - 260
EP  - 271
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Hamad, E. M.
A1  - Bilatto, S. E. R.
A1  - Adly, N. Y.
A1  - Correa, D. S.
A1  - Wolfrum, B.
A1  - Schöning, Michael Josef
A1  - Offenhäusser, A.
A1  - Yakushenko, A.
T1  - Inkjet printing of UV-curable adhesive and dielectric inks for microfluidic devices
JF  - Lab on a Chip
N2  - 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.
Y1  - 2016
U6  - https://doi.org/10.1039/C5LC01195G
SN  - 1473-0189
VL  - 16
IS  - 1
SP  - 70
EP  - 74
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  -