Droplet on Demand Generation & Droplet Splitting

App Note / Case Study

Published: March 6, 2015

Dropix delivers a Droplet-on-demand capability by creating programmable sequences of nanoliter and picoliter volume droplets. This application note demonstrates the Mitos Dropix® Splitting System to reproducibly generate nanoliter volume droplets, and subsequently split them into picoliter droplets of varying volumes. In tests, we show:

Setup of a differential flow between a positive displacement XS-Pump (in withdrawal mode with suction flow rate 5 – 15 μL/min) and a pressure driven P-Pump (pressure driven flow 5 – 15 μL/min).
Creation of a sequence of 200 nanoliter (nL) aqueous plugs, each separated by 200 nL of fluorocarbon oil.
Transport of the 200 nL plugs from Dropix to the flow focussing microfluidic device, and subsequent splitting of the plugs into many picoliter (pL) droplets. Depending on the split volume, the number of resulting droplets ranged from 100 up to 450.
The droplet size (90-180μm) and droplet production rate (0-75 Hz) range is parametrically characterized as a function of fluid flow rates.
The picoliter droplets are stored in a Storage Coil made up of a length of FEP tubing.