Fabrication of a microfluidic channel with differently modified surfaces with a two component approach

Abstract

We report on a two-component fabrication technique for microfluidic channels, allowing for different chemical or physical surface modifications of channel walls within one single channel. The two components are made of polydimethylsiloxane and prepared via soft lithography independently. After appropriate pre-treatment with the desired functions, the two parts are bonded together using oxygen plasma and a Fineplacer® lambda system. As a proof of concept, we present the combination of electroosmosis and opposing hydrodynamic flow in a microfluidic channel leading to different velocity presigns of the resulting flow on opposite channel walls, due to different surface modifications. These results indicate an intact Pluronic® F108 surface coating after assembly.