TY  - JOUR
A1  - Bronder, Thomas
A1  - Poghossian, Arshak
A1  - Scheja, S.
A1  - Wu, Chunsheng
A1  - Keusgen, M.
A1  - Schöning, Michael Josef
T1  - Electrostatic Detection of Unlabelled Single- and Double-stranded DNA Using Capacitive Field-effect Devices Functionalized with a Positively Charged Polyelectrolyte Layer
JF  - Procedia Engineering
N2  - Capacitive field-effect electrolyte-insulator-semiconductor sensors consisting of an Al-p-Si-SiO2 structure have been used for the electrical detection of unlabelled single- and double-stranded DNA (dsDNA) molecules by their intrinsic charge. A simple functionalization protocol based on the layer-by-layer (LbL) technique was used to prepare a weak polyelectrolyte/probe-DNA bilayer, followed by the hybridization with complementary target DNA molecules. Due to the flat orientation of the LbL-adsorbed DNA molecules, a high sensor signal has been achieved. In addition, direct label-free detection of in-solution hybridized dsDNA molecules has been studied.
Y1  - 2015
U6  - https://doi.org/10.1016/j.proeng.2015.08.710
SN  - 1877-7058
N1  - Eurosensors 2015
VL  - 120
SP  - 544
EP  - 547
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Akimbekov, Nuraly S.
A1  - Digel, Ilya
A1  - O’Heras, C.
A1  - Tastambek, K.T.
A1  - Savitskaya, I.S.
A1  - Ualyeva, P.S.
A1  - Mansurov, Z.A.
A1  - Zhubanova, A.A.
T1  - Adsorption of bacterial lipopol ysaccharides on carbonized ri ce husks obtained in the batch  experiments
JF  - KazNU Bulletin. Biology series
Y1  - 2015
SN  - 1563-0218
VL  - 60
IS  - No 1/2
SP  - 144
EP  - 148
ER  - 
TY  - JOUR
A1  - Wu, Chunsheng
A1  - Bronder, Thomas
A1  - Poghossian, Arshak
A1  - Werner, Frederik
A1  - Schöning, Michael Josef
T1  - Label-free detection of DNA using light-addressable potentiometric sensor modified with a positively charged polyelectrolyte layer
JF  - Nanoscale
N2  - A multi-spot (16 spots) light-addressable potentiometric sensor (MLAPS) consisting of an Al–p-Si–SiO2 structure modified with a weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)) was applied for the label-free electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization by the intrinsic molecular charge for the first time. To achieve a preferentially flat orientation of DNA strands and thus, to reduce the distance between the DNA charge and MLAPS surface, the negatively charged probe single-stranded DNAs (ssDNA) were electrostatically adsorbed onto the positively charged PAH layer using a simple layer-by-layer (LbL) technique. In this way, more DNA charge can be positioned within the Debye length, yielding a higher sensor signal. The surface potential changes in each spot induced due to the surface modification steps (PAH adsorption, probe ssDNA immobilization, hybridization with complementary target DNA (cDNA), non-specific adsorption of mismatched ssDNA) were determined from the shifts of photocurrent–voltage curves along the voltage axis. A high sensor signal of 83 mV was registered after immobilization of probe ssDNA onto the PAH layer. The hybridization signal increases from 5 mV to 32 mV with increasing the concentration of cDNA from 0.1 nM to 5 μM. In contrast, a small signal of 5 mV was recorded in the case of non-specific adsorption of fully mismatched ssDNA (5 μM). The obtained results demonstrate the potential of the MLAPS in combination with the simple and rapid LbL immobilization technique as a promising platform for the future development of multi-spot light-addressable label-free DNA chips with direct electrical readout.
Y1  - 2015
U6  - https://doi.org/10.1039/C4NR07225A
VL  - 14
IS  - 7
SP  - 6143
EP  - 6150
PB  - Royal Society of Chemistry (RSC)
CY  - Cambridge
ER  -