TY  - JOUR
A1  - Grinsven, Bart van
A1  - Bon, Natalie vanden
A1  - Strauven, Hannelore
A1  - Grieten, Lars
A1  - Murib, Mohammed
A1  - Jiménez Monroy, Kathia L.
A1  - Janssens, Stoffel D.
A1  - Haenen, Ken
A1  - Schöning, Michael Josef
A1  - Vermeeren, Veronique
A1  - Ameloot, Marcel
A1  - Michiels, Luc
A1  - Thoelen, Ronald
A1  - Ceuninck, Ward de
A1  - Wagner, Patrick
T1  - Heat-Transfer Resistance at Solid-Liquid Interfaces: A Tool for The Detection of Single Nucleotide Polymorphisms in DNA.
JF  - ACS Nano
N2  - In this article, we report on the heat-transfer resistance at interfaces as a novel, denaturation-based method to detect single-nucleotide polymorphisms in DNA. We observed that a molecular brush of double-stranded DNA grafted onto synthetic diamond surfaces does not notably affect the heat-transfer resistance at the solid-to-liquid interface. In contrast to this, molecular brushes of single-stranded DNA cause, surprisingly, a substantially higher heat-transfer resistance and behave like a thermally insulating layer. This effect can be utilized to identify ds-DNA melting temperatures via the switching from low- to high heat-transfer resistance. The melting temperatures identified with this method for different DNA duplexes (29 base pairs without and with built-in mutations) correlate nicely with data calculated by modeling. The method is fast, label-free (without the need for fluorescent or radioactive markers), allows for repetitive measurements, and can also be extended toward array formats. Reference measurements by confocal fluorescence microscopy and impedance spectroscopy confirm that the switching of heat-transfer resistance upon denaturation is indeed related to the thermal on-chip denaturation of DNA.
Y1  - 2012
U6  - http://dx.doi.org/10.1021/nn300147e
SN  - 1936-086X
VL  - 6
IS  - 3
SP  - 2712
EP  - 2721
PB  - ACS Publications
CY  - Washington, DC
ER  - 
TY  - JOUR
A1  - Schusser, Sebastian
A1  - Krischer, Maximillian
A1  - Bäcker, Matthias
A1  - Poghossian, Arshak
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Monitoring of the Enzymatically Catalyzed Degradation of Biodegradable Polymers by Means of Capacitive Field-Effect Sensors
JF  - Analytical Chemistry
N2  - Designing novel or optimizing existing biodegradable polymers for biomedical applications requires numerous tests on the effect of substances on the degradation process. In the present work, polymer-modified electrolyte–insulator–semiconductor (PMEIS) sensors have been applied for monitoring an enzymatically catalyzed degradation of polymers for the first time. The thin films of biodegradable polymer poly(d,l-lactic acid) and enzyme lipase were used as a model system. During degradation, the sensors were read-out by means of impedance spectroscopy. In order to interpret the data obtained from impedance measurements, an electrical equivalent circuit model was developed. In addition, morphological investigations of the polymer surface have been performed by means of in situ atomic force microscopy. The sensor signal change, which reflects the progress of degradation, indicates an accelerated degradation in the presence of the enzyme compared to hydrolysis in neutral pH buffer media. The degradation rate increases with increasing enzyme concentration. The obtained results demonstrate the potential of PMEIS sensors as a very promising tool for in situ and real-time monitoring of degradation of polymers.
Y1  - 2015
U6  - http://dx.doi.org/10.1021/acs.analchem.5b00617
SN  - 1520-6882
VL  - 87
IS  - 13
SP  - 6607
EP  - 6613
PB  - ACS Publications
CY  - Washington, DC
ER  -