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  - http://dx.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  - Schmitt, G.
A1  - Faßbender, F.
A1  - Lüth, H.
A1  - Schöning, Michael Josef
A1  - Buss, G.
A1  - Kranzmann, A.
A1  - Gramberg, U.
T1  - Korrosionsschutzwirkung von Passivierungsschichten am Beispiel eines Mikroelektrodenarrays
JF  - Werkstoffe für die Energietechnik / Symposium 3
Y1  - 1999
SN  - 3-527-29940-8
N1  - Serie Werkstoffwoche '98 ; 3
SP  - 345
EP  - 350
PB  - Wiley-VCH
CY  - Weinheim [u.a.]
ER  - 
TY  - JOUR
A1  - Schmitt, G.
A1  - Faßbender, F.
A1  - Lüth, H.
A1  - Schöning, Michael Josef
A1  - Schultze, J. W.
A1  - Buß, G.
T1  - Passivation and corrosion of microelectrode arrays
JF  - Materials and Corrosion. 51 (2000), H. 1
Y1  - 2000
SN  - 0947-5117
SP  - 20
EP  - 25
ER  - 
TY  - JOUR
A1  - Schmitt, G.
A1  - Schultze, J.-W.
A1  - Faßbender, F.
A1  - Buß, G.
A1  - Lüth, H.
A1  - Schöning, Michael Josef
T1  - Passivation and corrosion of microelectrode arrays
JF  - Electrochimica Acta. 44 (1999), H. 21-22
Y1  - 1999
SN  - 0013-4686
SP  - 3865
EP  - 3883
ER  - 
TY  - JOUR
A1  - Schmitt, G.
A1  - Werner, C.
A1  - Schöning, Michael Josef
T1  - Microelectrochemical efficiency evaluation of inhibitors for CO2 corrosion of carbon steel under high shear stress gradients
JF  - Corrosion 2002. Conference Proceedings. NACExpo, 57th Annual Conference and Exhibition, Denver, US, Apr 7-11, 2002
Y1  - 2002
N1  - Paper 02280
SP  - 1
EP  - 11
PB  - NACE International
CY  - Houston, Texas
ER  - 
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  - http://dx.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  - Schroth, P.
A1  - Lüth, H.
A1  - Hummel, Hans E.
A1  - Schütz, S.
A1  - Schöning, Michael Josef
T1  - Characterising an insect antenna as a receptor for a biosensor by means of impedance spectroscopy
JF  - 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
Y1  - 2001
SN  - 0-08-044014-2
SP  - 293
EP  - 297
PB  - Elsevier [u.a.]
CY  - Amsterdam [u.a.]
ER  - 
TY  - JOUR
A1  - Schroth, P.
A1  - Schöning, Michael Josef
A1  - Kordos, P.
A1  - Lüth, H.
A1  - Schütz, S.
A1  - Weißbecker, B.
A1  - Hummel, Hans E.
T1  - Insectbased BioFETs with improved signal characteristics
JF  - Biosensors & Bioelectronics. 14 (1999), H. 3
Y1  - 1999
SN  - 0956-5663
SP  - 303
EP  - 308
ER  - 
TY  - JOUR
A1  - Schroth, P.
A1  - Schöning, Michael Josef
A1  - Lüth, H.
A1  - Weißbecker, B.
A1  - Hummel, Hans E.
A1  - Schütz, S.
T1  - Extending the capabilities of an antenna/chip biosensor by employing various insect species
JF  - Sensors and  Actuators B. 78 (2001), H. 1-3
Y1  - 2001
SN  - 0925-4005
SP  - 1
EP  - 5
ER  - 
TY  - JOUR
A1  - Schroth, P.
A1  - Schöning, Michael Josef
A1  - Lüth, H.
A1  - Weißbecker, B.
A1  - Hummel, Hans E.
A1  - Schütz, S.
T1  - Extending the capabilities of an antenna/chip biosensor by employing various insect species
JF  - Proceedings : Copenhagen, Denmark, 27 - 30 August 2000 / [ed.: R. de Reus ...]
Y1  - 2000
SN  - 87-89935-50-0
N1  - Eurosensors ; (14, 2000, København) ; Eurosensors ; (14 : ; 2000.08.27-30 : ; Copenhagen) ; European Conference on Solid-State Transducers ; (14 : ; 2000.08.27-30 : ; Copenhagen)
SP  - 27
EP  - 30
PB  - MIC, Mikroelektronik Centret
CY  - Lyngby, Denmark
ER  -