[Langmuir] Autonomous Control of Fluids in Wide Surface Tension Range in Microfluidics
In this paper, we report the preparation of anisotropic wetting surfaces that could control various liquids’ wetting behavior in wide surface tension range (from water to oil), which could be employed as a platform for flowing control of liquids in microfluidics (MFs). The anisotropic wetting surfaces are chemistry-asymmetric “Janus” silicon cylinder arrays (Si-CAs) which are fabricated via selecting and regulating the functional groups on the surface of each cylinder unit. Liquids (in wide surface tension range) wet in a unidirectional manner along the direction which was modified by group with large surface energy. Through introducing the Janus structure into a T-shaped pattern and integrating it with an identical T-shaped poly(dimethylsiloxane) (PDMS) microchannel, the as-prepared chips can be utilized to perform as surface tension admeasuring apparatus or one-way valve for liquids in wide surface tension range, even oil. Furthermore, because of the excellent ability in controlling the flowing behavior of liquids in wide surface tension range in open system or microchannel, the anisotropic wetting surfaces are potential candidates to be applied both in open MFs and conventional MFs, and would broaden the application fields of MFs.
Peng Ge, Shuli Wang, Yongshun Liu, Wendong Liu, Nianzuo Yu, Jianglei Zhang, Huaizhong Shen, Junhu Zhang, and Bai Yang Langmuir, Just Accepted Manuscript DOI: 10.1021/acs.langmuir.7b01934 Publication Date (Web): July 6, 2017 Copyright © 2017 American Chemical Society