PORTABLE, 3D-PRINTED PNEUMATIC TIMERS FOR PRECISE AND FLEXIBLE NANOLITER DROPLET CONTROL WITHOUT THE NEED FOR ELECTRICAL POWER

Affordable 3D printers were used to print modular pneumatic logic gates, which can be operated with a single vacuum input.A droplet generator, where the droplet sizes were controlled using a 12-ring pneumatic delay buffer (inverters) as well as XOR and AND gates to select buffer outputs, created precise millisecond (ms) range pulses to open a microfluidic valve and control droplet size.With the pneumatic delay buffer, the timing of the valve's operation could be delayed in the range of 20 -150 ms with 7 -10 ms precision, allowing control of valves on the droplet generating device to make droplets from 12 -40 nL droplet control and 1 nL precision.This precise, easyto-use system is inexpensive and can be operated without any electrical power.