Changes of Inertial Focusing Position in a Triangular Channel Depending on Droplet Deformability and Size.

Area of Science:

• Microfluidics
• Biophysics
• Cellular Mechanics

Background:

• Cell separation using inertial microfluidics often uses solid particles, but real cells are deformable, reducing efficiency.
• Understanding the deformability-induced lift force is crucial for improving cell separation in microfluidic devices.

Purpose of the Study:

• To investigate how cell deformability affects inertial focusing positions in a triangular microchannel.
• To explore the influence of Reynolds number (Re), deformability, and droplet size on focusing behavior.

Main Methods:

• Experimental analysis of viscous droplet focusing in a triangular microchannel.
• Systematic variation of Reynolds number (Re), droplet deformability, and droplet size.

Main Results:

• Increasing Re and decreasing droplet size cause focusing positions to split and shift towards sidewalls.
• Higher deformability increases the threshold droplet size for focusing position splitting.
• Droplet focusing position is strongly dependent on deformability, even for droplets of the same size.

Conclusions:

• Cell deformability is a critical factor in inertial microfluidic focusing.
• Demonstrated the feasibility of deformability-based cell separation using distinct focusing positions of MCF10a and MCF7 cells.