Project R-6750

Utilizing interfacial impedance- and heat-transfer phenomena in advanced monitoring- and switching devices (Research)

Electrochemical impedance spectroscopy (EIS) is an established technique for probing the conductive and dielectric properties of matter in wide frequency ranges. Applications are numerous and cover the determination of salinity of sea water equally well as the detection of neurotransmitters and proteins in blood- and food samples. The applicants have found a 'thermal counterpart' to impedance spectroscopy in 2012 in which the electrical current is replaced by a thermal current: This 'heat-transfer method HTM' has proven useful in various bio-analytical tasks and advantages over impedance spectroscopy are seen in the fact that HTM can operate easily with electrically insulating sensor-chip materials and non-conductive liquids. Within this proposal, we will aim at integrating EIS and advanced thermal-wave techniques (2- and 3-omega principle) into a dual methodology to be employed in two fields: i) The monitoring of degradation processes of biocompatible polymers and ii) monitoring of bacterial growth in in-vitro wound models under chemical and electronic stimuli. Moreover, we will utilize the dual approach in order to study switching effects of thermal- and electrical currents through iii) pH-responsive polymer layers and iv) molecular brushes of DNA. This will result in novel devices based on tunable interfaces with possible applications in the emerging fields of enzymatic chemical computing and 'heat-tronics', in which heat flow replaces electrical currents.

01 January 2016 - 31 December 2019