Microfluidics Reactor is a droplet-based lab-on-a-chip built in a school lab with no specialised equipment. Chip masters are printed on an LCD resin printer at 50 µm accuracy and cast in PDMS; four synchronized peristaltic pumps driven by an Arduino push the oil and reactant phases through 300 µm channels, and a digital microscope with a Python and OpenCV tracker measures droplet size and speed in real time.

I led hardware and software on a team of four at Letovo in 2023–24: the pump system, four peristaltic pumps in a 3D-printed enclosure at about $48 each, less than half the price of a syringe pump, the Arduino PWM control and the droplet tracker in Python and OpenCV; the team cast the chips. It forms stable droplets of 50 to 150 µm at 0.5 to 2 mm/s, and the procedure is written up so another school can repeat it.