The Heat-Transfer Method: From benchtop setup to handheld device

Abstract

In an urge to fulfil the increasing demand for reliable economical biosensor readout techniques, researchers at IMO-IMOMEC developed the Heat-Transfer Method. With this method it is possible to perform bioanalytical tasks by closely monitoring heat transfer trough a detection layer. Multiple promising results have been obtained with the initial setup that was built around this novel readout technique. Examples of which are the detection of specific biologically relevant molecules in liquids, and the detection of Single-Nucleotide Polymorphisms in DNA. In order to monitor heat-transfer, the initial setup requires two thermocouples. One on each side of the detection layer. Hereby the thermocouples are not only a bottleneck for accuracy, they also form a hurdle for the miniaturization of the setup. To overcome this problem, recently a new sensor design based on the Transient Plane Source (TPS) was presented. With this sensor design, thermocouples are no longer required since temperature information can be derived from the electrical resistance of the sensor. Initial tests on the new sensor, performed with a benchtop power supply, have showed promising results. Therefore, this new sensor design will be further exploited and miniaturized. Since a smaller sensor requires a less powerful power supply, it is also possible to miniaturize the control hardware of the sensor. In this regard, work will be done to create a custom voltage controlled current source to replace the bulky benchtop power supply. This way we can not only reduce the overall cost of the setup, but ultimately we can transform the original benchtop HTM setup into a handheld device which can be used for a broad range of applications.