Osmosis-induced hydrodynamic centering of W/O/W double emulsion droplets for quasi-concentric microcapsule/microsphere fabrication

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

2 Scopus Citations
View graph of relations

Detail(s)

Original languageEnglish
Article number132428
Journal / PublicationColloids and Surfaces A: Physicochemical and Engineering Aspects
Volume677
Issue numberPart B
Online published19 Sept 2023
Publication statusPublished - 20 Nov 2023

Abstract

Water-in-oil-in-water (W/O/W) double emulsion droplets are a typical colloidal system applied in various practical fields. However, certain high-specification applications necessitate exact geometric homogeneity in terms of both shell diameter and thickness. Despite achieving uniformity in shell diameter, on-chip microfluidic emulsification always leads to an eccentric phenomenon due to innate density differences of the droplet solution. At the same time, the current regulation methods have multiple limitations, including their applicability, regulatory scope, and objective restrictions. Herein, we propose an off-chip osmosis-induced hydrodynamic method to accurately regulate the eccentricity of W/O/W double emulsion droplets. The rational selection of hypertonic osmosis can energize the droplets and induce inward transmembrane water flux. This flow helps to reposition the droplet core to align concentrically with the shell, regardless of the initial dimension and eccentricity of the droplets. As the osmotic induction reduces due to the dilution of the inner solute molar concentration, the optimal droplet configuration can be achieved when osmosis-induced hydrodynamic regulation sufficiently counteracts the adverse effects of droplet solution density difference. The microcapsules can thus be produced by instant UV polymerization of the regulated double emulsion droplets, and the silica microspheres with fine geometric homogeneity can be prepared through further heat treatment, which is expected to meet the stringent morphological requirements in practical applications. © 2023 Elsevier B.V. All rights reserved.

Research Area(s)

  • Hydrodynamic regulation, Microfluidics, Microspheres, Osmosis, W/O/W double emulsion droplet

Citation Format(s)

Osmosis-induced hydrodynamic centering of W/O/W double emulsion droplets for quasi-concentric microcapsule/microsphere fabrication. / Wu, Hao; Jiang, Tianyi; Wu, Wenlong et al.
In: Colloids and Surfaces A: Physicochemical and Engineering Aspects, Vol. 677, No. Part B, 132428, 20.11.2023.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review