Manipulation of aqueous droplets in two-phase flow system using patterned surface wettability

Abstract

This work reports the fabrication and experimentation of microfluidic systems with patterned surface wettability. The system is fabricated from two components; a cyclic olefin copolymer (COC) substrate and a Polydimethylsiloxane (PDMS) element that includes a microchannel. The wettability of the COC substrate is altered using standard microfabrication processes. Graphene oxide hydrophilic film is patterned on the surface of the hydrophobic COC substrate using plasma-enhanced liftoff approach. The device is used to manipulate dye-water droplets dispersed in silicone oil. The movement of the water droplets inside the device is found to be influenced by the GO film patterned inside the channel.