Biosensor applications based on thermal boundary resistance
Impedimetric detection is a label-free biosensing method that is known already since decades. In 2012, we proposed the heat-transfer method HTM as an alternative concept in which electronic- or ionic currents are replaced by a thermal current. A special advantage is seen in the fact that thermal currents can also penetrate electrically isolating sensor-chip materials and receptor layers. A first application of HTM was the thermal on-chip denaturation of double-stranded DNA on synthetic diamond- and sapphire chips, allowing to assess the stability of these molecules with respect to single-nucleotide polymorphisms. HTM was moreover employed in the selective detection of neurotransmitters (histamine, serotonin, nicotine) using molecularly imprinted polymers as receptors and in protein detection with aptamer-based receptors. By using surface-imprinted polymers as synthetic receptor layers, HTM has turned out to be especially versatile for the characterization and identification of cells, including human cancer cells and various types of bacteria. Practically all effects (DNA denaturation, binding of cells, proteins, and small molecules) go along with an increase of the thermal boundary resistance between the solid sensor chip and the supernatant liquid. In case of lipid-vesicle layers, the phase transition from the ripple- to the liquid-disordered phase results in a fully reversible jump of the thermal boundary resistance. We will address the possible mechanism behind the strong thermal-resistance effect of nanoscale layers at interfaces and summarize also novel experimental developments based on the original HTM method.
This presentation has not yet been uploaded.
No handouts have been uploaded.
Christ Glorieux (POC,Primary Presenter), KU Leuven, email@example.com;