title: Controlled Generation of Ultrathin-Shell Double Emulsions and Studies on Their Stability.
abstract: Double emulsions with a hierarchical core-shell structure have great potential in various applications, but their broad use is limited by their instability. To improve stability, water-in-oil-in-water (W/O/W) emulsions with an ultrathin oil layer of several hundred nanometres were produced by using a microcapillary device. The effects of various parameters on the generation of ultrathin-shell double emulsions and their droplet size were investigated, including the proper combinations of inner, middle and outer phases, flow rates and surfactants. The surfactant in the middle oil phase was found to be critical for the formation of the ultrathin-shell double emulsions. Furthermore, the stability of these double emulsions can be notably improved by increasing the concentration of the surfactant, and they can be stable for months. This opens up new opportunities for their future applications in cosmetics, foods and pharmaceuticals.
authors.affiliation: Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia.|John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, 02138, USA.
authors.forename: Chun-Xia
authors.initials: CX
authors.lastname: Zhao
authors.affiliation: John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, 02138, USA.|State Key Laboratory of Fluid Power and Mechatronic Systems, Institute of Process Equipment, College of Chemical and Biological Engineering, Zhejiang University, Zheda Road No.38, Hangzhou, 310027, P. R. China.
authors.forename: Dong
authors.initials: D
authors.lastname: Chen
authors.affiliation: Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia.
authors.forename: Yue
authors.initials: Y
authors.lastname: Hui
authors.affiliation: John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, 02138, USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Weitz
authors.affiliation: Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia.
authors.forename: Anton P J
authors.initials: APJ
authors.lastname: Middelberg
mesh_terms: D004655:Emulsions / Q000138:chemical synthesis / Q000737:chemistry; D009821:Oils / Q000737:chemistry; D010316:Particle Size; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D004655:Emulsions; D009821:Oils; D013501:Surface-Active Agents; D014867:Water
keywords: emulsions; encapsulation; glass capillary devices; interfaces; microfluidics