Interplay of diffusio- and thermo-osmotic flows generated by single light stimulus
- Flow control is a highly relevant topic for micromanipulation of colloidal particles in microfluidic applications. Here, we report on a system that combines two-surface bound flows emanating from thermo-osmotic and diffusio-osmotic mechanisms. These opposing flows are generated at a gold surface immersed into an aqueous solution containing a photo-sensitive surfactant, which is irradiated by a focused UV laser beam. At low power of incoming light, diffusio-osmotic flow due to local photo-isomerization of the surfactant dominates, resulting in a flow pattern oriented away from the irradiated area. In contrast, thermo-osmotic flow takes over due to local heating of the gold surface at larger power, consequently inducing a flow pointing toward the hotspot. In this way, this system allows one to reversibly switch from outward to inward liquid flow with an intermittent range of zero flow at which tracer particles undergo thermal motion by just tuning the laser intensity only. Our work, thus, demonstrates an optofluidic system for flowFlow control is a highly relevant topic for micromanipulation of colloidal particles in microfluidic applications. Here, we report on a system that combines two-surface bound flows emanating from thermo-osmotic and diffusio-osmotic mechanisms. These opposing flows are generated at a gold surface immersed into an aqueous solution containing a photo-sensitive surfactant, which is irradiated by a focused UV laser beam. At low power of incoming light, diffusio-osmotic flow due to local photo-isomerization of the surfactant dominates, resulting in a flow pattern oriented away from the irradiated area. In contrast, thermo-osmotic flow takes over due to local heating of the gold surface at larger power, consequently inducing a flow pointing toward the hotspot. In this way, this system allows one to reversibly switch from outward to inward liquid flow with an intermittent range of zero flow at which tracer particles undergo thermal motion by just tuning the laser intensity only. Our work, thus, demonstrates an optofluidic system for flow generation with a high degree of controllability that is necessary to transport particles precisely to desired locations, thereby opening innovative possibilities to generate advanced microfluidic applications.…
Verfasserangaben: | Valeriia Muraveva, Marek BekirORCiDGND, Nino Lomadze, Robert GroßmannORCiD, Carsten BetaORCiDGND, Svetlana SanterORCiDGND |
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DOI: | https://doi.org/10.1063/5.0090229 |
ISSN: | 0003-6951 |
ISSN: | 1077-3118 |
Titel des übergeordneten Werks (Englisch): | Applied physics letters |
Verlag: | American Institute of Physics |
Verlagsort: | Melville |
Publikationstyp: | Wissenschaftlicher Artikel |
Sprache: | Englisch |
Datum der Erstveröffentlichung: | 07.06.2022 |
Erscheinungsjahr: | 2022 |
Datum der Freischaltung: | 05.01.2023 |
Band: | 120 |
Ausgabe: | 23 |
Aufsatznummer: | 231905 |
Seitenanzahl: | 5 |
Fördernde Institution: | DFG, Germany [SA1657/18-1]; International Max Planck Research School on; Multiscale Bio-Systems (IMPRS), Potsdam, Germany |
Organisationseinheiten: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Physik und Astronomie |
DDC-Klassifikation: | 5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik |
Peer Review: | Referiert |