1. Fabrication and operation of the microfluidic device. (A) A microfluidic design is double printed (approximately 1.6× larger than the final
desired dimensions) onto Shrinky Dink film using a laser printer. (B) The printed patterns are cut to size and submerged in hot oil (150 °C) until
the film shrinks completely (30−60 s). (C) The shrunken design is removed quickly from the oil and gently flattened between two glass plates. (D)
The cleaned and dry design is taped to the bottom of a Petri dish, and (E) PDMS elastomer is poured in the dish to completely cover the design. (F)
A vacuum pump is used to degas the PDMS elastomer before it is cured in a 60 °C oven overnight. (G) Once the PDMS has fully cured, the
microfluidic device is cut to the desired size using a razor. Inlets and outlets are created using a biopsy punch, and the final device is assembled by
attaching the PDMS device to a glass slide with double-sided tape. (H) Liquid samples are added to the device (shown here as yellow and blue
droplets covering the inlets) using a pipet. Flow is achieved by attaching a syringe to the outlet of the device using a short piece of flexible tubing.
Gently pulling the syringe plunger creates a vacuum that draws the samples through the device toward the outlet.