[Biomicrofluidics] Stable microfluidic flow focusing using hydrostatics
We present a simple technique to generate stable hydrodynamically focused flows by driving the flow with hydrostatic pressure from liquid columns connected to the inlets of a microfluidic device. Importantly, we compare the focused flows generated by hydrostatic pressure and classical syringe pump driven flows and find that the stability of the hydrostatic pressure driven technique is significantly better than the stability achieved via syringe pumps, providing fluctuation-free focused flows that are suitable for sensitive microfluidic flow cytometry applications. We show that the degree of flow focusing with the hydrostatic method can be accurately controlled by the simple tuning of the liquid column heights. We anticipate that this approach to stable flow focusing will find many applications in microfluidic cytometry technologies.
Vaskar Gnyawali1,2,3, Mohammadali Saremi1,2,3, Michael C. Kolios2,3,4, and Scott S. H. Tsai1,2,3,a)Hide Affiliations 1Department of Mechanical and Industrial Engineering, Ryerson University, Toronto, Canada 2Institute for Biomedical Engineering, Science and Technology (iBEST), Toronto, Canada 3Keenan Research Centre, St. Michaels Hospital, Toronto, Canada 4Department of Physics, Ryerson University, Toronto, Canada a)Electronic mail: firstname.lastname@example.org