Temperature dependence of diffusiophoresis via a novel microfluidic approach. Issue 10 (21st April 2022)

• Record Type: Journal Article
• Authors: Shah, Parth R.; Tan, Huanshu; Taylor, David; Tang, Xiaoyu; Shi, Nan; Mashat, Afnan; Abdel-Fattah, Amr; Squires, Todd M.
• Is Part Of: Lab on a chip. Volume 22:Issue 10(2022)
• Page Start: 1980
• Page End: 1988
• Publication Date: 2022-04-21
• Subjects: Miniature electronic equipment -- Periodicals; Combinatorial chemistry -- Periodicals; Biotechnology -- Periodicals; 543.0813
• DOI: 10.1039/d1lc00916h
• Languages: English
• ISSNs: 1473-0197

Abstract

Abstract : Our manuscript uses a novel microfluidic approach to measure diffusiophoretic mobilities as a function of temperature, which match with the theoretical predictions based on electrophoretically measured zeta potentials. Abstract : The temperature dependence of the diffusiophoretic mobility ( D DP ) is investigated experimentally and compared with theoretical predictions. These systematic measurements were made possible by a new microfluidic approach that enables truly steady state gradients to be imposed, and direct and repeatable measurements of diffusiophoretic migration to be made over hours-long time scales. Diffusiophoretic mobilities were measured for fluorescent, negatively charged polystyrene particles under NaCl gradients, at temperatures ranging from 20 °C to 70 °C. Measured D DP values were found to increase monotonically with temperature, and to agree, both qualitatively and relatively quantitatively, with theoretical predictions based on electrophoretically-measured zeta potentials. These results provide confidence that existing diffusiophoresis theories can accurately predict DP mobilities over a range of temperatures. More broadly, we anticipate our new microfluidic approach will facilitate and enable new tests of diffusiophoretic phenomena under a wide range of physical and chemical conditions.