Experimental Demonstration on the Leakage-Free Surface-Driven Capillary Flow of Red Dye

Abstract

In this work, two individual SU-8 based glass microfluidic devices are fabricated by the maskless lithography and indirect bonding technique. Commercially available red-colored food dye is used as the working liquid. Microfluidic leakage is observed between the glass lid and SU-8 based microchannel substrate due to the improper indirect bonding technique. Leakage-free surface-driven capillary flow is observed due to the proper indirect bonding technique. CMOS camera is used to capture and record each surface-driven microfluidic flow of red dye. This work will be useful to fabricate the microfluidic lab-on-a-chip systems by the negative photoresist SU-8.