Fig 1. Schematic steps in micropattern substrate fabrication process.

A micropattern of alternating PEG-gel and glass stripes is created by attaching a microfluidic chip to a clean microscope coverglass, reversibly bonding the device to the coverglass by overnight incubation at 60°C, filling microchannels of the devices with PEG-gel pre-polymer, purging O₂ in an N₂ chamber, cross-linking the PEG-gel by a UV-exposure, and detaching the microfluidic chip from the coverglass.