Abstract: This study introduces a thermophoretic lab-on-a-chip device to measure the Soret coefficient. We use resistive heating of a microwire on the chip to induce a temperature gradient, which is measured by fluorescence lifetime imaging microscopy (FLIM). To verify the functionality of the device, we used dyed polystyrene particles with a diameter of 25 nm. A confocal microscope is utilized to monitor the concentration profile of colloidal particles in the temperature field. Based on the measured temperature and concentration differences, we calculate the corresponding Soret coefficient. The same particles have been recently investigated with thermal diffusion forced Rayleigh scattering (TDFRS) and we find that the obtained Soret coefficients agree with literature results. This chip offers a simple way to study the thermophoretic behavior of biological systems in multicomponent buffer solutions quantitatively, which are difficult to study with optical methods solely relying on the refractive index contrast. Graphic abstract: [Figure not available: see fulltext.]
|Journal||European Physical Journal E|
|Publication status||Published - 2021 Oct|
Bibliographical noteFunding Information:
We thank Amirreza Gholivand, Pavlik Lettinga, Marisol Ripoll and Zihan Tan for fruitful discussions. We are grateful to Jan Dhont for inspiring ideas and his generous support of our work. Further, we thank Shilpa Mohanakumar for careful correction reading. This work was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2019R1A6A3A03033316).
© 2021, The Author(s).
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Surfaces and Interfaces