Characterization of Fluidic-Barrier-Based Particle Generation in Centrifugal Microfluidics

The fluidic barrier in centrifugal microfluidic platforms is a newly introduced concept for making multiple emulsions and microparticles. In this study, we focused on particle generation application to better characterize this method. Because the phenomenon is too fast to be captured experimentally, we employ theoretical models to show how liquid polymeric droplets pass a fluidic barrier before crosslinking. We explain how secondary flows evolve and mix the fluids within the droplets. From an experimental point of view, the effect of different parameters, such as the barrier length, source channel width, and rotational speed, on the particles' size and aspect ratio are investigated. It is demonstrated that the barrier length does not affect the particle's ultimate velocity. Unlike conventional air gaps, the barrier length does not significantly affect the aspect ratio of the produced microparticles. Eventually, we broaden this concept to two source fluids and study the importance of source channel geometry, barrier length, and rotational speed in generating two-fluid droplets.

Automated summary

The fluidic barrier in centrifugal microfluidic platforms is a newly introduced concept that is used for making multiple emulsions and microparticles. This study focuses on the application of particle generation to better understand this method. Theoretical models are used to explain how liquid polymeric droplets pass through a fluidic barrier, and experimental investigations are conducted to explore the effects of different parameters on the size and aspect ratio of the particles. The concept is further extended to two-source fluids, and the importance of source channel geometry, barrier length, and rotational speed in generating two-fluid droplets is studied.