TY  - JOUR
A1  - Molinnus, Denise
A1  - Hardt, Gabriel
A1  - Siegert, Petra
A1  - Willenberg, Holger S.
A1  - Poghossian, Arshak
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Detection of Adrenaline in Blood Plasma as Biomarker for Adrenal Venous Sampling
JF  - Electroanalysis
N2  - An amperometric bi-enzyme biosensor based on substrate recycling principle for the amplification of the sensor signal has been developed for the detection of adrenaline in blood. Adrenaline can be used as biomarker verifying successful adrenal venous sampling procedure. The adrenaline biosensor has been realized via modification of a galvanic oxygen sensor with a bi-enzyme membrane combining a genetically modified laccase and a pyrroloquinoline quinone-dependent glucose dehydrogenase. The measurement conditions such as pH value and temperature were optimized to enhance the sensor performance. A high sensitivity and a low detection limit of about 0.5–1 nM adrenaline have been achieved in phosphate buffer at pH 7.4, relevant for measurements in blood samples. The sensitivity of the biosensor to other catecholamines such as noradrenaline, dopamine and dobutamine has been studied. Finally, the sensor has been successfully applied for the detection of adrenaline in human blood plasma.
Y1  - 2018
U6  - https://doi.org/10.1002/elan.201800026
SN  - 1521-4109
VL  - 30
IS  - 5
SP  - 937
EP  - 942
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Oberländer, Jan
A1  - Mayer, Marlena
A1  - Greeff, Anton
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Spore-based biosensor to monitor the microbicidal efficacy of gaseous hydrogen peroxide sterilization processes
JF  - Biosensors and Bioelectronics
N2  - In this work, a spore-based biosensor is evaluated to monitor the microbicidal efficacy of sterilization processes applying gaseous hydrogen peroxide (H2O2). The sensor is based on interdigitated electrode structures (IDEs) that have been fabricated by means of thin-film technologies. Impedimetric measurements are applied to study the effect of sterilization process on spores of Bacillus atrophaeus. This resilient microorganism is commonly used in industry to proof the sterilization efficiency. The sensor measurements are accompanied by conventional microbiological challenge tests, as well as morphological characterizations with scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The sensor measurements are correlated with the microbiological test routines. In both methods, namely the sensor-based and microbiological one, a tailing effect has been observed. The results are evaluated and discussed in a three-dimensional calibration plot demonstrating the sensor's suitability to enable a rapid process decision in terms of a successfully performed sterilization.
Y1  - 2018
U6  - https://doi.org/10.1016/j.bios.2017.12.045
SN  - 0956-5663
VL  - 104
SP  - 87
EP  - 94
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - BOOK
A1  - Molinnus, Denise
T1  - Integration of biomolecular logic principles with electronic transducers on a chip
Y1  - 2018
PB  - Philipps-Universität / Fachbereich Pharmazie
CY  - Marburg/Lahn
ER  - 
TY  - JOUR
A1  - Figueroa-Miranda, Gabriela
A1  - Feng, Lingyan
A1  - Shiu, Simon Chi-Chin
A1  - Dirkzwager, Roderick Marshall
A1  - Cheung, Yee-Wai
A1  - Tanner, Julian Alexander
A1  - Schöning, Michael Josef
A1  - Offenhäusser, Andreas
A1  - Mayer, Dirk
T1  - Aptamer-based electrochemical biosensor for highly sensitive and selective malaria detection with adjustable dynamic response range and reusability
JF  - Sensor and Actuators B: Chemical
N2  - 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.
Y1  - 2018
U6  - https://doi.org/10.1016/j.snb.2017.07.117
SN  - 0925-4005
VL  - 255
IS  - P1
SP  - 235
EP  - 243
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Miyamoto, Koichiro
A1  - Seki, Kosuke
A1  - Suto, Takeyuki
A1  - Werner, Frederik
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
A1  - Yoshinobu, Tatsuo
T1  - Improved spatial resolution of the chemical imaging sensor with a hybrid illumination that suppresses lateral diffusion of photocarriers
JF  - Sensor and Actuators B: Chemical
N2  - The chemical imaging sensor is a semiconductor-based chemical sensor capable of visualizing pH and ion distributions. The spatial resolution depends on the lateral diffusion of photocarriers generated by illumination of the semiconductor substrate. In this study, two types of optical setups, one based on a bundle of optical fibers and the other based on a binocular tube head, were developed to project a hybrid illumination of a modulated light beam and a ring-shaped constant illumination onto the sensor plate. An improved spatial resolution was realized by the ring-shaped constant illumination, which suppressed lateral diffusion of photocarriers by enhanced recombination due to the increased carrier concentration.
Y1  - 2018
U6  - https://doi.org/10.1016/j.snb.2018.07.016
SN  - 0925-4005
VL  - 273
SP  - 1328
EP  - 1333
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Röhlen, Desiree
A1  - Pilas, Johanna
A1  - Dahmen, Markus
A1  - Keusgen, Michael
A1  - Selmer, Thorsten
A1  - Schöning, Michael Josef
T1  - Toward a Hybrid Biosensor System for Analysis of Organic and Volatile Fatty Acids in Fermentation Processes
JF  - Frontiers in Chemistry
N2  - Monitoring of organic acids (OA) and volatile fatty acids (VFA) is crucial for the control of anaerobic digestion. In case of unstable process conditions, an accumulation of these intermediates occurs. In the present work, two different enzyme-based biosensor arrays are combined and presented for facile electrochemical determination of several process-relevant analytes. Each biosensor utilizes a platinum sensor chip (14 × 14 mm²) with five individual working electrodes. The OA biosensor enables simultaneous measurement of ethanol, formate, d- and l-lactate, based on a bi-enzymatic detection principle. The second VFA biosensor provides an amperometric platform for quantification of acetate and propionate, mediated by oxidation of hydrogen peroxide. The cross-sensitivity of both biosensors toward potential interferents, typically present in fermentation samples, was investigated. The potential for practical application in complex media was successfully demonstrated in spiked sludge samples collected from three different biogas plants. Thereby, the results obtained by both of the biosensors were in good agreement to the applied reference measurements by photometry and gas chromatography, respectively. The proposed hybrid biosensor system was also used for long-term monitoring of a lab-scale biogas reactor (0.01 m³) for a period of 2 months. In combination with typically monitored parameters, such as gas quality, pH and FOS/TAC (volatile organic acids/total anorganic carbonate), the amperometric measurements of OA and VFA concentration could enhance the understanding of ongoing fermentation processes.
Y1  - 2018
U6  - https://doi.org/10.3389/fchem.2018.00284
IS  - 6
PB  - Frontiers
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Rodrigues, Raul T.
A1  - Morais, Paulo V.
A1  - Nordi, Cristina S. F.
A1  - Schöning, Michael Josef
A1  - Siqueira Jr., José R.
A1  - Caseli, Luciano
T1  - Carbon Nanotubes and Algal Polysaccharides To Enhance the Enzymatic Properties of Urease in Lipid Langmuir-Blodgett Films
JF  - Langmuir
N2  - Algal polysaccharides (extracellular polysaccharides) and carbon nanotubes (CNTs) were adsorbed on dioctadecyldimethylammonium bromide Langmuir monolayers to serve as a matrix for the incorporation of urease. The physicochemical properties of the supramolecular system as a monolayer at the air–water interface were investigated by surface pressure–area isotherms, surface potential–area isotherms, interfacial shear rheology, vibrational spectroscopy, and Brewster angle microscopy. The floating monolayers were transferred to hydrophilic solid supports, quartz, mica, or capacitive electrolyte–insulator–semiconductor (EIS) devices, through the Langmuir–Blodgett (LB) technique, forming mixed films, which were investigated by quartz crystal microbalance, fluorescence spectroscopy, and field emission gun scanning electron microscopy. The enzyme activity was studied with UV–vis spectroscopy, and the feasibility of the thin film as a urea sensor was essayed in an EIS sensor device. The presence of CNT in the enzyme–lipid LB film not only tuned the catalytic activity of urease but also helped to conserve its enzyme activity. Viability as a urease sensor was demonstrated with capacitance–voltage and constant capacitance measurements, exhibiting regular and distinctive output signals over all concentrations used in this work. These results are related to the synergism between the compounds on the active layer, leading to a surface morphology that allowed fast analyte diffusion owing to an adequate molecular accommodation, which also preserved the urease activity. This work demonstrates the feasibility of employing LB films composed of lipids, CNT, algal polysaccharides, and enzymes as EIS devices for biosensing applications.
Y1  - 2018
U6  - https://doi.org/10.1021/acs.langmuir.7b04317
SN  - 1520-5827
VL  - 34
IS  - 9
SP  - 3082
EP  - 3093
PB  - ACS Publications
CY  - Washington, DC
ER  - 
TY  - BOOK
A1  - Schöning, Michael Josef
A1  - Poghossian, Arshak
T1  - Label-free biosensing: advanced materials, devices and applications
Y1  - 2018
SN  - 978-3-319-75219-8
PB  - Springer
CY  - Cham
ER  - 
TY  - CHAP
A1  - Yoshinobu, Tatsuo
A1  - Krause, Steffi
A1  - Miyamoto, Ko-ichiro
A1  - Werner, Frederik
A1  - Poghossian, Arshak
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - (Bio-)chemical Sensing and Imaging by LAPS and SPIM
T2  - Label-free biosensing: advanced materials, devices and applications
N2  - The light-addressable potentiometric sensor (LAPS) and scanning photo-induced impedance microscopy (SPIM) are two closely related methods to visualise the distributions of chemical species and impedance, respectively, at the interface between the sensing surface and the sample solution. They both have the same field-effect structure based on a semiconductor, which allows spatially resolved and label-free measurement of chemical species and impedance in the form of a photocurrent signal generated by a scanning light beam. In this article, the principles and various operation modes of LAPS and SPIM, functionalisation of the sensing surface for measuring various species, LAPS-based chemical imaging and high-resolution sensors based on silicon-on-sapphire substrates are described and discussed, focusing on their technical details and prospective applications.
KW  - Chemical imaging
KW  - Field-effect device
KW  - Light-addressable potentiometric sensor
KW  - Potentiometry
Y1  - 2018
SN  - 978-3-319-75219-8
SP  - 103
EP  - 132
PB  - Springer
CY  - Cham
ER  - 
TY  - CHAP
A1  - Schöning, Michael Josef
A1  - Wagner, Torsten
A1  - Poghossian, Arshak
A1  - Miyamoto, K.I.
A1  - Werner, C.F.
A1  - Krause, S.
A1  - Yoshinobu, T.
T1  - Light-addressable potentiometric sensors for (bio-)chemical sensing and imaging
T2  - Encyclopedia of Interfacial Chemistry: Surface Science and Electrochemistry. Vol. 7
Y1  - 2018
SN  - 9780128097397
SP  - 295
EP  - 308
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - CHAP
A1  - Schöning, Michael Josef
A1  - Poghossian, Arshak
T1  - Enzyme und Biosensorik
T2  - Einführung in die Enzymtechnologie
N2  - Enzymbasierte Biosensoren finden seit mehr als fünf Jahrzehnten einen prosperierenden Wachstumsmarkt und werden zunehmend auch in biotechnologischen Prozessen eingesetzt. In diesem Kapitel werden, ausgehend vom Sensorbegriff und typischen Kenngrößen für Biosensoren (Abschn. 18.1), elektrochemische Enzym-Biosensoren vorgestellt und deren typischen Einsatzgebiete diskutiert (Abschn. 18.2). Ein Blick über den „Tellerrand“ hinaus zeigt alternative Transduktorprinzipien (Abschn. 18.3) und führt abschließend in aktuelle Forschungstrends ein (Abschn. 18.4).
Y1  - 2018
SN  - 978-3-662-57619-9
U6  - https://doi.org/10.1007/978-3-662-57619-9_18
SP  - 323
EP  - 347
PB  - Springer Spektrum
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Rabehi, Amine
A1  - Garlan, Benjamin
A1  - Achtsnicht, Stefan
A1  - Krause, Hans-Joachim
A1  - Offenhäusser, Andreas
A1  - Ngo, Kieu
A1  - Neveu, Sophie
A1  - Graff-Dubois, Stephanie
A1  - Kokabi, Hamid
T1  - Magnetic detection structure for Lab-on-Chip applications based on the frequency mixing technique
JF  - Sensors
N2  - A magnetic frequency mixing technique with a set of miniaturized planar coils was investigated for use with a completely integrated Lab-on-Chip (LoC) pathogen sensing system. The system allows the detection and quantification of superparamagnetic beads. Additionally, in terms of magnetic nanoparticle characterization ability, the system can be used for immunoassays using the beads as markers. Analytical calculations and simulations for both excitation and pick-up coils are presented; the goal was to investigate the miniaturization of simple and cost-effective planar spiral coils. Following these calculations, a Printed Circuit Board (PCB) prototype was designed, manufactured, and tested for limit of detection, linear response, and validation of theoretical concepts. Using the magnetic frequency mixing technique, a limit of detection of 15 µg/mL of 20 nm core-sized nanoparticles was achieved without any shielding.
KW  - Lab-on-Chip
KW  - magnetic sensing
KW  - frequency mixing
KW  - superparamagnetic nanoparticles
KW  - magnetic beads
Y1  - 2018
U6  - https://doi.org/10.3390/s18061747
SN  - 1424-8220
VL  - 18
IS  - 6
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Morais, Paulo V.
A1  - Silva, Anielle C. A.
A1  - Dantas, Noelio O.
A1  - Schöning, Michael Josef
A1  - Siqueira, José R., Jr.
T1  - Hybrid Layer‐by‐Layer Film of Polyelectrolytes‐Embedded Catalytic CoFe2O4 Nanocrystals as Sensing Units in Capacitive Electrolyte‐Insulator‐Semiconductor Devices
JF  - physica status solidi a : applications and materials sciences
Y1  - 2019
U6  - https://doi.org/10.1002/pssa.201900044
VL  - 216
IS  - 1900044
SP  - 1
EP  - 9
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Breuer, Lars
A1  - Pilas, Johanna
A1  - Guthmann, Eric
A1  - Schöning, Michael Josef
A1  - Thoelen, Ronald
A1  - Wagner, Torsten
T1  - Towards light-addressable flow control: responsive hydrogels with incorporated graphene oxide as laser-driven actuator structures within microfluidic channels
JF  - Sensor and Actuators B: Chemical
Y1  - 2019
U6  - https://doi.org/10.1016/j.snb.2019.02.086
SN  - 0925-4005
VL  - 288
SP  - 579
EP  - 585
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Cornelis, Peter
A1  - Givanoudi, Stella
A1  - Yongabi, Derick
A1  - Iken, Heiko
A1  - Duwé, Sam
A1  - Deschaume, Olivier
A1  - Robbens, Johan
A1  - Dedecker, Peter
A1  - Bartic, Carmen
A1  - Wübbenhorst, Michael
A1  - Schöning, Michael Josef
A1  - Heyndrickx, Marc
A1  - Wagner, Patrick
T1  - Sensitive and specific detection of E. coli using biomimetic receptors in combination with a modified heat-transfer method
JF  - Biosensors and Bioelectronics
Y1  - 2019
U6  - https://doi.org/10.1016/j.bios.2019.04.026
SN  - 0956-5663
VL  - 136
SP  - 97
EP  - 105
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Geissler, Hanno
A1  - Schöning, Michael Josef
T1  - Rapid methods and sensors for milk quality monitoring and spoilage detection
JF  - Biosensors and Bioelectronics
Y1  - 2019
U6  - https://doi.org/10.1016/j.bios.2019.04.040
SN  - 0956-5663
VL  - 140
IS  - Article 111272
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Dantism, Shahriar
A1  - Röhlen, Desiree
A1  - Wagner, Torsten
A1  - Wagner, P.
A1  - Schöning, Michael Josef
T1  - A LAPS-based differential sensor for parallelized metabolism monitoring of various bacteria
JF  - Sensors
N2  - Monitoring the cellular metabolism of bacteria in (bio)fermentation processes is crucial to control and steer them, and to prevent undesired disturbances linked to metabolically inactive microorganisms. In this context, cell-based biosensors can play an important role to improve the quality and increase the yield of such processes. This work describes the simultaneous analysis of the metabolic behavior of three different types of bacteria by means of a differential light-addressable potentiometric sensor (LAPS) set-up. The study includes Lactobacillus brevis, Corynebacterium glutamicum, and Escherichia coli, which are often applied in fermentation processes in bioreactors. Differential measurements were carried out to compensate undesirable influences such as sensor signal drift, and pH value variation during the measurements. Furthermore, calibration curves of the cellular metabolism were established as a function of the glucose concentration or cell number variation with all three model microorganisms. In this context, simultaneous (bio)sensing with the multi-organism LAPS-based set-up can open new possibilities for a cost-effective, rapid detection of the extracellular acidification of bacteria on a single sensor chip. It can be applied to evaluate the metabolic response of bacteria populations in a (bio)fermentation process, for instance, in the biogas fermentation process.
Y1  - 2019
U6  - https://doi.org/10.3390/s19214692
SN  - 1424-8220
VL  - 19
IS  - 21
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Karschuck, T. L.
A1  - Filipov, Y.
A1  - Bollella, P.
A1  - Schöning, Michael Josef
A1  - Katz, E.
T1  - Not-XOR (NXOR) logic gate based on an enzyme-catalyzed reaction
JF  - International Journal of Unconventional Computing
N2  - Enzyme-catalyzed reactions have been designed to mimic various Boolean logic gates in the general framework of unconventional biomolecular computing. While some of the logic gates, particularly OR, AND, are easy to realize with biocatalytic reactions and have been reported in numerous publications, some other, like NXOR, are very challenging and have not been realized yet with enzyme reactions. The paper reports on a novel approach to mimicking the NXOR logic gate using the bell-shaped enzyme activity dependent on pH values. Shifting pH from the optimum value to the acidic or basic values by using acid or base inputs (meaning 1,0 and 0,1 inputs) inhibits the enzyme reaction, while keeping the optimum pH (assuming 0,0 and 1,1 input combinations) preserves a high enzyme activity. The challenging part of the present approach is the selection of an enzyme with a well-demonstrated bell-shape activity dependence on the pH value. While many enzymes can satisfy this condition, we selected pyrroloquinoline quinone (PQQ)-dependent glucose dehydrogenase as this enzyme has the optimum pH center-located on the pH scale allowing the enzyme activity change by the acidic and basic pH shift from the optimum value corresponding to the highest activity. The present NXOR gate is added to the biomolecular “toolbox” as a new example of Boolean logic gates based on enzyme reactions.
Y1  - 2019
SN  - 1548-7199
VL  - 14
IS  - 3-4
SP  - 235
EP  - 242
PB  - Old City Publishing
CY  - Philadelphia
ER  - 
TY  - JOUR
A1  - Arreola, Julio
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Toward an immobilization method for spore-based biosensors in oxidative environment
JF  - Electrochimica Acta
Y1  - 2019
U6  - https://doi.org/10.1016/j.electacta.2019.01.148
VL  - 302
SP  - 394
EP  - 401
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Bronder, Thomas
A1  - Poghossian, Arshak
A1  - Jessing, Max P.
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Surface regeneration and reusability of label-free DNA biosensors based on weak polyelectrolyte-modified capacitive field-effect structures
JF  - Biosensors and Bioelectronics
Y1  - 2019
U6  - https://doi.org/10.1016/j.bios.2018.11.019
SN  - 0956-5663
VL  - 126
SP  - 510
EP  - 517
PB  - Elsevier
CY  - Amsterdam
ER  -