TY  - JOUR
A1  - Gamella, Maria
A1  - Zakharchenko, Andrey
A1  - Guz, Nataliia
A1  - Masi, Madeline
A1  - Minko, Sergiy
A1  - Kolpashchikov, Dmitry M.
A1  - Iken, Heiko
A1  - Poghossian, Arshak
A1  - Schöning, Michael Josef
A1  - Katz, Evgeny
T1  - DNA computing system activated by electrochemically triggered DNA realease from a polymer-brush-modified electrode array
JF  - Electroanalysis
N2  - 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.
Y1  - 2017
U6  - http://dx.doi.org/10.1002/elan.201600389
SN  - 1521-4109
VL  - 29
IS  - 2
SP  - 398
EP  - 408
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Bäcker, Matthias
A1  - Koch, Claudia
A1  - Eiben, Sabine
A1  - Geiger, Fania
A1  - Eber, Fabian
A1  - Gliemann, Hartmut
A1  - Poghossian, Arshak
A1  - Wege, Christina
A1  - Schöning, Michael Josef
T1  - Tobacco mosaic virus as enzyme nanocarrier for electrochemical biosensors
JF  - Sensors and Actuators B: Chemical
N2  - The conjunction of (bio-)chemical recognition elements with nanoscale biological building blocks such as virus particles is considered as a very promising strategy for the creation of biohybrids opening novel opportunities for label-free biosensing. This work presents a new approach for the development of biosensors using tobacco mosaic virus (TMV) nanotubes or coat proteins (CPs) as enzyme nanocarriers. Sensor chips combining an array of Pt electrodes loaded with glucose oxidase (GOD)-modified TMV nanotubes or CP aggregates were used for amperometric detection of glucose as a model system for the first time. The presence of TMV nanotubes or CPs on the sensor surface allows binding of a high amount of precisely positioned enzymes without substantial loss of their activity, and may also ensure accessibility of their active centers for analyte molecules. Specific and efficient immobilization of streptavidin-conjugated GOD ([SA]-GOD) complexes on biotinylated TMV nanotubes or CPs was achieved via bioaffinity binding. These layouts were tested in parallel with glucose sensors with adsorptively immobilized [SA]-GOD, as well as [SA]-GOD crosslinked with glutardialdehyde, and came out to exhibit superior sensor performance. The achieved results underline a great potential of an integration of virus/biomolecule hybrids with electronic transducers for future applications in biosensorics and biochips.
Y1  - 2017
U6  - http://dx.doi.org/10.1016/j.snb.2016.07.096
SN  - 0925-4005
VL  - 238
SP  - 716
EP  - 722
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Bronder, Thomas
A1  - Poghossian, Arshak
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Label-free detection of double-stranded DNA molecules with polyelectrolyte-modified capacitive field-effect sensors
T1  - Markierungsfreie Detektion doppelsträngiger DNA Moleküle mit Hilfe von Polyelektrolyt-modifizierten kapazitiven Feldeffekt-Sensoren
JF  - tm - Technisches Messen
N2  - In this study, polyelectrolyte-modified field-effect-based electrolyte-insulator-semiconductor (EIS) devices have been used for the label-free electrical detection of double-stranded deoxyribonucleic acid (dsDNA)molecules. The sensor-chip functionalization with a positively charged polyelectrolyte layer provides the possibility of direct adsorptive binding of negatively charged target DNA oligonucleotides onto theSiO2-chip surface.EIS sensors can be utilized as a tool to detect surface-charge changes; the electrostatic adsorption of oligonucleotides onto the polyelectrolyte layer leads to a measureable surface-potential change. Signals of 39mV have been recorded after the incubation with the oligonucleotide solution. Besides the electrochemical experiments, the successful adsorption of dsDNA onto the polyelectrolyte layer has been verified via fluorescence microscopy. The presented results demonstrate that the signal recording of EISchips, which are modified with a polyelectrolyte layer, canbe used as a favorable approach for a fast, cheap and simple detection method for dsDNA.
Y1  - 2017
U6  - http://dx.doi.org/10.1515/teme-2017-0015
VL  - 84
IS  - 10
SP  - 628
EP  - 634
PB  - De Gruyter
CY  - Oldenbourg
ER  -