TY  - JOUR
A1  - Scholl, Fabio
A1  - Morais, Paulo
A1  - Gabriel, Rayla
A1  - Schöning, Michael Josef
A1  - Siqueira, Jose Roberto, Jr.
A1  - Caseli, Luciano
T1  - Carbon nanotubes arranged as smart interfaces in lipid Langmuir-Blodgett films enhancing the enzymatic properties of penicillinase for biosensing applications
JF  - Applied Materials & Interfaces
N2  - In this paper, carbon nanotubes (CNTs) were incorporated in penicillinase-phospholipid Langmuir and Langmuir–Blodgett (LB) films to enhance the enzyme catalytic properties. Adsorption of the penicillinase and CNTs at dimyristoylphosphatidic acid (DMPA) monolayers at the air–water interface was investigated by surface pressure–area isotherms, vibrational spectroscopy, and Brewster angle microscopy. The floating monolayers were transferred to solid supports through the LB technique, forming mixed DMPA-CNTs-PEN films, which were investigated by quartz crystal microbalance, vibrational spectroscopy, and atomic force microscopy. Enzyme activity was studied with UV–vis spectroscopy and the feasibility of the supramolecular device nanostructured as ultrathin films were essayed in a capacitive electrolyte–insulator–semiconductor (EIS) sensor device. The presence of CNTs in the enzyme–lipid LB film not only tuned the catalytic activity of penicillinase but also helped conserve its enzyme activity after weeks, showing increased values of activity. Viability as penicillin 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 may be related not only to the nanostructured system provided by the film, but also to the synergism between the compounds on the active layer, leading to a surface morphology that allowed a fast analyte diffusion because of an adequate molecular accommodation, which also preserved the penicillinase activity. This work therefore demonstrates the feasibility of employing LB films composed of lipids, CNTs, and enzymes as EIS devices for biosensing applications.
Y1  - 2017
U6  - https://doi.org/10.1021/acsami.7b08095
SN  - 1944-8252
VL  - 9
IS  - 36
SP  - 31054
EP  - 31066
PB  - ACS
CY  - Washington
ER  - 
TY  - JOUR
A1  - Tran, Linda
A1  - Mottaghy, K.
A1  - Arlt-Körfer, Sabine
A1  - Waluga, Christian
A1  - Behbahani, Mehdi
T1  - An experimental study of shear-dependent human platelet adhesion and underlying protein-binding mechanisms in a cylindrical Couette system
JF  - Biomedizinische Technik
Y1  - 2017
U6  - https://doi.org/10.1515/bmt-2015-0034
SN  - 0013-5585
VL  - 62
IS  - 4
SP  - 383
EP  - 392
PB  - De Gruyter
CY  - Berlin
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  - Morais, Paulo V.
A1  - Gomes, Vanderley F., Jr.
A1  - Silva, Anielle C. A.
A1  - Dantas, Noelio O.
A1  - Schöning, Michael Josef
A1  - Siqueira, José R., Jr.
T1  - Nanofilm of ZnO nanocrystals/carbon nanotubes as biocompatible layer for enzymatic biosensors in capacitive field-effect devices
JF  - Journal of Materials Science
N2  - The incorporation of nanomaterials that are biocompatible with different types of biological compounds has allowed the development of a new generation of biosensors applied especially in the biomedical field. In particular, the integration of film-based nanomaterials employed in field-effect devices can be interesting to develop biosensors with enhanced properties. In this paper, we studied the fabrication of sensitive nanofilms combining ZnO nanocrystals and carbon nanotubes (CNTs), prepared by means of the layer-by-layer (LbL) technique, in a capacitive electrolyte-insulator-semiconductor (EIS) structure for detecting glucose and urea. The ZnO nanocrystals were incorporated in a polymeric matrix of poly(allylamine) hydrochloride (PAH), and arranged with multi-walled CNTs in a LbL PAH-ZnO/CNTs film architecture onto EIS chips. The electrochemical characterizations were performed by capacitance–voltage and constant capacitance measurements, while the morphology of the films was characterized by atomic force microscopy. The enzymes glucose oxidase and urease were immobilized on film’s surface for detection of glucose and urea, respectively. In order to obtain glucose and urea biosensors with optimized amount of sensitive films, we investigated the ideal number of bilayers for each detection system. The glucose biosensor showed better sensitivity and output signal for an LbL PAH-ZnO/CNTs nanofilm with 10 bilayers. On the other hand, the urea biosensor presented enhanced properties even for the first bilayer, exhibiting high sensitivity and output signal. The presence of the LbL PAH-ZnO/CNTs films led to biosensors with better sensitivity and enhanced response signal, demonstrating that the adequate use of nanostructured films is feasible for proof-of-concept biosensors with improved properties that may be employed for biomedical applications.
Y1  - 2017
U6  - https://doi.org/10.1007/s10853-017-1369-y
SN  - 1573-4803
VL  - 52
IS  - 20
SP  - 12314
EP  - 12325
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Röhlen, Desiree
A1  - Pilas, Johanna
A1  - Schöning, Michael Josef
A1  - Selmer, Thorsten
T1  - Development of an amperometric biosensor platform for the combined determination of l-Malic, Fumaric, and l-Aspartic acid
JF  - Applied Biochemistry and Biotechnology
N2  - Three amperometric biosensors have been developed for the detection of L-malic acid, fumaric acid, and L -aspartic acid, all based on the combination of a malate-specific dehydrogenase (MDH, EC 1.1.1.37) and diaphorase (DIA, EC 1.8.1.4). The stepwise expansion of the malate platform with the enzymes fumarate hydratase (FH, EC 4.2.1.2) and aspartate ammonia-lyase (ASPA, EC 4.3.1.1) resulted in multi-enzyme reaction cascades and, thus, augmentation of the substrate spectrum of the sensors. Electrochemical measurements were carried out in presence of the cofactor β-nicotinamide adenine dinucleotide (NAD+) and the redox mediator hexacyanoferrate (III) (HCFIII). The amperometric detection is mediated by oxidation of hexacyanoferrate (II) (HCFII) at an applied potential of + 0.3 V vs. Ag/AgCl. For each biosensor, optimum working conditions were defined by adjustment of cofactor concentrations, buffer pH, and immobilization procedure. Under these improved conditions, amperometric responses were linear up to 3.0 mM for L-malate and fumarate, respectively, with a corresponding sensitivity of 0.7 μA mM−1 (L-malate biosensor) and 0.4 μA mM−1 (fumarate biosensor). The L-aspartate detection system displayed a linear range of 1.0–10.0 mM with a sensitivity of 0.09 μA mM−1. The sensor characteristics suggest that the developed platform provides a promising method for the detection and differentiation of the three substrates.
Y1  - 2017
U6  - https://doi.org/10.1007/s12010-017-2578-1
SN  - 1559-0291
VL  - 183
SP  - 566
EP  - 581
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Pilas, Johanna
A1  - Yazici, Yasemen
A1  - Selmer, Thorsten
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Optimization of an amperometric biosensor array for simultaneous measurement of ethanol, formate, d- and l-lactate
JF  - Electrochimica Acta
N2  - The immobilization of NAD+-dependent dehydrogenases, in combination with a diaphorase, enables the facile development of multiparametric sensing devices. In this work, an amperometric biosensor array for simultaneous determination of ethanol, formate, d- and l-lactate is presented. Enzyme immobilization on platinum thin-film electrodes was realized by chemical cross-linking with glutaraldehyde. The optimization of the sensor performance was investigated with regard to enzyme loading, glutaraldehyde concentration, pH, cofactor concentration and temperature. Under optimal working conditions (potassium phosphate buffer with pH 7.5, 2.5 mmol L-1 NAD+, 2.0 mmol L-1 ferricyanide, 25 °C and 0.4% glutaraldehyde) the linear working range and sensitivity of the four sensor elements was improved. Simultaneous and cross-talk free measurements of four different metabolic parameters were performed successfully. The reliable analytical performance of the biosensor array was demonstrated by application in a clarified sample of inoculum sludge. Thereby, a promising approach for on-site monitoring of fermentation processes is provided.
KW  - Simultaneous determination
KW  - Enzymatic biosensor
KW  - Diaphorase
KW  - Dehydrogenase
Y1  - 2017
U6  - https://doi.org/10.1016/j.electacta.2017.07.119
SN  - 0013-4686
VL  - 251
SP  - 256
EP  - 262
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Albanna, Walid
A1  - Lueke, Jan Niklas
A1  - Sjapic, Volha
A1  - Kotliar, Konstantin
A1  - Hescheler, Jürgen
A1  - Clusmann, Hans
A1  - Sjapic, Sergej
A1  - Alpdogan, Serdan
A1  - Schneider, Toni
A1  - Schubert, Gerrit Alexander
A1  - Neumaier, Felix
T1  - Electroretinographic Assessment of Inner Retinal Signaling in the Isolated and Superfused Murine Retina
JF  - Current Eye Research
Y1  - 2017
U6  - https://doi.org/10.1080/02713683.2017.1339807
SN  - 1460-2202
IS  - Article in press
SP  - 1
EP  - 9
PB  - Taylor & Francis
CY  - London
ER  - 
TY  - JOUR
A1  - Rietsch, Stefan H. G.
A1  - Pfaffenrot, Viktor
A1  - Bitz, Andreas
A1  - Orzada, Stephan
A1  - Brunheim, Sascha
A1  - Lazik-Palm, Andrea
A1  - Theysohn, Jens M.
A1  - Ladd, Mark E.
A1  - Quick, Harald H.
A1  - Kraff, Oliver
T1  - An 8-channel transceiver 7-channel receive RF coil setup for high SNR ultrahigh-field MRI of the shoulder at 7T
JF  - Medical Physics
Y1  - 2017
U6  - https://doi.org/10.1002/mp.12612
SN  - 0094-2405
IS  - Article in press
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Kotliar, Konstantin
A1  - Hauser, Christine
A1  - Ortner, Marion
A1  - Muggenthaler, Claudia
A1  - Diehl-Schmid, Janine
A1  - Angermann, Susanne
A1  - Hapfelmeier, Alexander
A1  - Schmaderer, Christoph
A1  - Grimmer, Timo
T1  - Altered neurovascular coupling as measured by optical imaging: a biomarker for Alzheimer’s disease
JF  - Scientific Reports
Y1  - 2017
U6  - https://doi.org/10.1038/s41598-017-13349-5
SN  - 2045-2322
N1  - Article 12906
VL  - 7
IS  - 1
SP  - 1
EP  - 11
PB  - Springer Nature
CY  - Cham
ER  - 
TY  - JOUR
A1  - Breuer, Lars
A1  - Mang, Thomas
A1  - Schöning, Michael Josef
A1  - Thoelen, Ronald
A1  - Wagner, Torsten
T1  - Investigation of the spatial resolution of a laser-based stimulation process for light-addressable hydrogels with incorporated graphene oxide by means of IR thermography
JF  - Sensors and Actuators A: Physical
Y1  - 2017
U6  - https://doi.org/10.1016/j.sna.2017.11.031
SN  - 0924-4247
VL  - 268
SP  - 126
EP  - 132
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Demmer, Julius K.
A1  - Chowdhury, Nilanjan Pal
A1  - Selmer, Thorsten
A1  - Ermler, Ulrich
A1  - Buckel, Wolfgang
T1  - The semiquinone swing in the bifurcating electron transferring flavoprotein/butyryl-CoA dehydrogenase complex from Clostridium difficile
JF  - Nature Communications
Y1  - 2017
U6  - https://doi.org/10.1038/s41467-017-01746-3
SN  - 2041-1723
N1  - Article number 1577
VL  - 8
IS  - 1
SP  - 1
EP  - 10
ER  - 
TY  - JOUR
A1  - Werkhausen, Amelie
A1  - Albracht, Kirsten
A1  - Cronin, Neil J.
A1  - Meier, Rahel
A1  - Mojsen-Moeller, Jens
A1  - Seynnes, Olivier R.
T1  - Modulation of muscle-tendon interaction in the human triceps surae during an energy dissipation task
JF  - Journal of Experimental Biology
Y1  - 2017
U6  - https://doi.org/10.1242/jeb.164111
SN  - 0022-0949
VL  - 220
IS  - 22
SP  - 4141
EP  - 4149
ER  - 
TY  - JOUR
A1  - Höttges, Jörg
T1  - QKan - Management of drainage system data with QGIS
JF  - Free and Open Source Software for Geospatial (FOSS4G) Conference Proceedings
Y1  - 2017
VL  - 17
IS  - Article 13
SP  - 95
EP  - 100
ER  - 
TY  - JOUR
A1  - Srivastava, A.
A1  - Chahar, V.
A1  - Sharma, V.
A1  - Sun, Y.
A1  - Bol, R.
A1  - Knolle, F.
A1  - Schnug, E.
A1  - Hoyler, Friedrich
A1  - Naskar, N.
A1  - Lahiri, S.
A1  - Patnaik, R.
T1  - Study of uranium toxicity using low-background gamma-ray spectrometry
JF  - Journal of Radioanalytical and Nuclear Chemistry
Y1  - 2017
U6  - https://doi.org/10.1007/s10967-017-5466-9
SN  - 1588-2780
IS  - Online first
SP  - 1
EP  - 7
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Garibaldi, F.
A1  - Beging, Stefan
A1  - Canese, R.
A1  - Carpinelli, G.
A1  - Clinthorne, N.
A1  - Colilli, S.
A1  - Cosentino, L.
A1  - Finocchiaro, P.
A1  - Giuliani, F.
A1  - Gricia, M.
A1  - Lucentini, M.
A1  - Majewski, S.
A1  - Monno, E.
A1  - Musico, P.
A1  - Santavenere, F.
A1  - Tödter, J.
A1  - Wegener, Hans-Peter
A1  - Ziemons, Karl
T1  - A novel TOF-PET MRI detector for diagnosis and follow up of the prostate cancer
JF  - European Physical Journal Plus
Y1  - 2017
U6  - https://doi.org/10.1140/epjp/i2017-11662-x
SN  - 2190-5444
VL  - 132
IS  - 9
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Orzada, Stephan
A1  - Bitz, Andreas
A1  - Johst, Sören
A1  - Gratz, Marcel
A1  - Völker, Maximilian N.
A1  - Kraff, Oliver
A1  - Abuelhaija, Ashraf
A1  - Fiedler, Thomas M.
A1  - Solbach, Klaus
A1  - Quick, Harald H.
A1  - Ladd, Mark E.
T1  - Analysis of an integrated 8-Channel Tx/Rx body array for use as a body coil in 7-Tesla MRI
JF  - Frontiers in Physics
Y1  - 2017
U6  - https://doi.org/10.3389/fphy.2017.00017
SN  - 2296-424X
N1  - Article number 17
VL  - 5
IS  - Jun
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  - Eckert, Alexander
A1  - Rudolph, Tobias
A1  - Guo, Jiaqi
A1  - Mang, Thomas
A1  - Walther, Andreas
T1  - Exceptionally Ductile and Tough Biomimetic Artificial Nacre with Gas Barrier Function
JF  - Advanced Materials
N2  - Synthetic mimics of natural high-performance structural materials have shown great and partly unforeseen opportunities for the design of multifunctional materials. For nacre-mimetic nanocomposites, it has remained extraordinarily challenging to make ductile materials with high stretchability at high fractions of reinforcements, which is however of crucial importance for flexible barrier materials. Here, highly ductile and tough nacre-mimetic nanocomposites are presented, by implementing weak, but many hydrogen bonds in a ternary nacre-mimetic system consisting of two polymers (poly(vinyl amine) and poly(vinyl alcohol)) and natural nanoclay (montmorillonite) to provide efficient energy dissipation and slippage at high nanoclay content (50 wt%). Tailored interactions enable exceptional combinations of ductility (close to 50% strain) and toughness (up to 27.5 MJ m⁻³). Extensive stress whitening, a clear sign of high internal dynamics at high internal cohesion, can be observed during mechanical deformation, and the materials can be folded like paper into origami planes without fracture. Overall, the new levels of ductility and toughness are unprecedented in highly reinforced bioinspired nanocomposites and are of critical importance to future applications, e.g., as barrier materials needed for encapsulation and as a printing substrate for flexible organic electronics.
Y1  - 2018
U6  - https://doi.org/10.1002/adma.201802477
VL  - 30
IS  - 32
SP  - Article number 1802477
PB  - Wiley-VCH
ER  - 
TY  - JOUR
A1  - Lapitan, Denis G.
A1  - Rogatkin, Dmitrii A.
A1  - Persheyev, Sydulla K.
A1  - Kotliar, Konstantin
T1  - False spectra formation in the differential two-channel scheme of the laser Doppler flowmeter
JF  - Biomedizinische Technik
N2  - Noise in the differential two-channel scheme of a classic laser Doppler flowmetry (LDF) instrument was studied. Formation of false spectral components in the output signal due to beating of electrical signals in the differential amplifier was found out. The improved block-diagram of the flowmeter was developed allowing to reduce the noise.
Y1  - 2018
U6  - https://doi.org/10.1515/bmt-2017-0060
SN  - 0013-5585
VL  - 63
IS  - 4
SP  - 439
EP  - 444
PB  - De Gruyter
CY  - Berlin
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  -