TY  - JOUR
A1  - Wu, Chunsheng
A1  - Poghossian, Arshak
A1  - Bronder, Thomas
A1  - Schöning, Michael Josef
T1  - Sensing of double-stranded DNA molecules by their intrinsic molecular charge using the light-addressable potentiometric sensor
JF  - Sensors and Actuators B: Chemical
N2  - A multi-spot light-addressable potentiometric sensor (LAPS), which belongs to the family of semiconductor field-effect devices, was applied for label-free detection of double-stranded deoxyribonucleic acid (dsDNA) molecules by their intrinsic molecular charge. To reduce the distance between the DNA charge and sensor surface and thus, to enhance the electrostatic coupling between the dsDNA molecules and the LAPS, the negatively charged dsDNA molecules were electrostatically adsorbed onto the gate surface of the LAPS covered with a positively charged weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)). The surface potential changes in each spot of the LAPS, induced by the layer-by-layer adsorption of a PAH/dsDNA bilayer, were recorded by means of photocurrent-voltage and constant-photocurrent measurements. In addition, the surface morphology of the gate surface before and after consecutive electrostatic adsorption of PAH and dsDNA layers was studied by atomic force microscopy measurements. Moreover, fluorescence microscopy was used to verify the successful adsorption of dsDNA molecules onto the PAH-modified LAPS surface. A high sensor signal of 25 mV was registered after adsorption of 10 nM dsDNA molecules. The lower detection limit is down to 0.1 nM dsDNA. The obtained results demonstrate that the PAH-modified LAPS device provides a convenient and rapid platform for the direct label-free electrical detection of in-solution hybridized dsDNA molecules.
KW  - Layer-by-layer adsorption
KW  - Poly(allylamine hydrochloride)
KW  - Label-free detection
KW  - DNA biosensor
KW  - LAPS
KW  - Field effect
Y1  - 2016
U6  - http://dx.doi.org/10.1016/j.snb.2016.02.004
SN  - 0925-4005
IS  - 229
SP  - 506
EP  - 512
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - CHAP
A1  - Poghossian, Arshak
A1  - Bronder, Thomas
A1  - Scheja, S.
A1  - Wu, Chunsheng
A1  - Metzger-Boddien, C.
A1  - Keusgen, M.
A1  - Schöning, Michael Josef
T1  - Label-free Electrostatic Detection of DNA Amplification by PCR Using Capacitive Field-effect Devices
T2  - Procedia Engineering
N2  - A capacitive field-effect EIS (electrolyte-insulator-semiconductor) sensor modified with a positively charged weak polyelectrolyte of poly(allylamine hydrochloride) (PAH)/single-stranded probe DNA (ssDNA) bilayer has been used for a label-free electrostatic detection of pathogen-specific DNA amplification via polymerase chain reaction (PCR). The sensor is able to distinguish between positive and negative PCR solutions, to detect the existence of target DNA amplicons in PCR samples and thus, can be used as tool for a quick verification of DNA amplification and the successful PCR process.
Y1  - 2016
U6  - http://dx.doi.org/10.1016/j.proeng.2016.11.512
SN  - 1877-7058
N1  - Proceedings of the 30th anniversary Eurosensors Conference – Eurosensors 2016, 4-7. Sepember 2016, Budapest, Hungary
VL  - Vol. 168
SP  - 514
EP  - 517
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Schöning, Michael Josef
A1  - Bronder, Thomas
A1  - Wu, Chunsheng
A1  - Scheja, Sabrina
A1  - Jessing, Max
A1  - Metzger-Boddien, Christoph
A1  - Keusgen, Michael
A1  - Poghossian, Arshak
T1  - Label-Free DNA Detection with Capacitive Field-Effect Devices—Challenges and Opportunities
JF  - Proceedings
N2  - Field-effect EIS (electrolyte-insulator-semiconductor) sensors modified with a positively charged weak polyelectrolyte layer have been applied for the electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization by the intrinsic molecular charge. The EIS sensors are able to detect the existence of target DNA amplicons in PCR (polymerase chain reaction) samples and thus, can be used as tool for a quick verification of DNA amplification and the successful PCR process. Due to their miniaturized setup, compatibility with advanced micro- and nanotechnologies, and ability to detect biomolecules by their intrinsic molecular charge, those sensors can serve as possible platform for the development of label-free DNA chips. Possible application fields as well as challenges and limitations will be discussed.
Y1  - 2017
U6  - http://dx.doi.org/10.3390/proceedings1080719
SN  - 2504-3900
N1  - This article belongs to the Proceedings of "Proceedings of the 5th International Symposium on Sensor Science (I3S 2017)"
VL  - 1
IS  - 8
SP  - Artikel 719
PB  - MDPI
CY  - Basel
ER  -