Authors: Dr. Kai Seng, KOH, Dr. Jun, HE
In this paper, we present a modular microfluidic platform for lab-on-chip (LoC) device that enable a single liquid droplet split into 3 daughter droplets which was never being reported elsewhere. Using Poly(dimethylsiloxane) (PDMS) as structural material, a bilayer of 3D microchannel design consisting of constriction formed by trifurcating junction is constructed via rapid prototyping method. The design of the trifurcating 3D microstructure consists of a top layer that has a pair of 1 cm radius curvature microstructure junctions aligned to a bottom layer that contains straight microchannel with a Tjunction upstream. Both top and bottom microchannel layer has a constant microchannel width and height of 250 micrometer and 100 micrometer respectively. The preliminary result of this novel microstructure shows that the droplet size formed at all three junctions have range from 152-214 micrometer feret diameter at continuous phase flowrate range of 4-10 microliter per minute. Besides, the coefficient of variation (CV) of droplets formed is approximately 7% and the droplet size ratio, which is the size of droplet formed to channel width for all three daughter droplets formed, is found to be in the range of 0.61 to 0.85.
Keywords: microfluidic; droplet splitting; lab on chip (loc); curvature junction splitting; modular microfluidic platform