Schematic overview of the fabrication of PDMS chips. (a) The process starts by fabricating a silicon master mold—with typical dimensions of 10 centimeter in diameter and 0.5 millimeter thickness—with microfluidic structures on top. (b) A viscous mixture of PDMS oligomers and crosslinker is poured on top of the mold and allowed to form a flexible, crosslinked network. (c) The slab of PDMS is peeled off of the mold and bound to a glass or PDMS surface to produce closed microfluidic channels. (d) The microfluidic device is ready to be used. Prior to binding to the surface, holes can be punched in the slab of PDMS to reach the resulting microfluidic channel.
