Jump to main content
Jump to site search

Issue 4, 2021
Previous Article Next Article

Phase separation of a nonionic surfactant aqueous solution in a standing surface acoustic wave for submicron particle manipulation

Author affiliations

Abstract

Acoustic manipulation of submicron particles in a controlled manner has been challenging to date because of the increased contribution of acoustic streaming, which leads to fluid mixing and homogenization. This article describes the patterning of submicron particles and the migration of their patterned locations from pressure nodes to antinodes in a non-ionic surfactant (Tween 20) aqueous solution in a conventional standing surface acoustic wave field with a wavelength of 150 μm. Phase separation of the aqueous surfactant solution occurs when they are exposed to acoustic waves, probably due to the “clouding behavior” of non-ionic surfactant. The generated surfactant precipitates are pushed to the pressure antinodes due to the negative acoustic contrast factor relative to water. Compared with the mixing appearance in pure water media, the patterning behavior of submicron particles with a diameter of 300 nm dominated by acoustic radiation force is readily apparent in an aqueous solution with 2% volumetric concentration of Tween 20 surfactant, thanks to the suppression effect of acoustic streaming in inhomogeneous fluids. These submicron particles are first pushed to acoustic pressure nodes and then are migrated to antinodes where the surfactant precipitates stay. More attractively, the migration of acoustically patterned locations is not only limited to submicron particles, but also occurs to micrometer-sized particles in solutions with higher surfactant concentrations. These findings open up a novel avenue for controllable acoustic manipulation.

Graphical abstract: Phase separation of a nonionic surfactant aqueous solution in a standing surface acoustic wave for submicron particle manipulation

Back to tab navigation

Supplementary files

Article information


Submitted
29 Sep 2020
Accepted
11 Dec 2020
First published
14 Dec 2020

Lab Chip, 2021,21, 660-667
Article type
Communication

Phase separation of a nonionic surfactant aqueous solution in a standing surface acoustic wave for submicron particle manipulation

L. Zhao, P. Niu, E. Casals, M. Zeng, C. Wu, Y. Yang, S. Sun, Z. Zheng, Z. Wang, Y. Ning, X. Duan and W. Pang, Lab Chip, 2021, 21, 660
DOI: 10.1039/D0LC00986E

Social activity

Search articles by author

Spotlight

Advertisements