Synopsis: Sorting Blood Cells via Their Stiffness

A proposed modification to a microfluidic cell-sorting device could separate cells by their deformability, an important marker for several diseases.
Synopsis figure
Z. Zhang et al., Phys. Rev. Fluids (2019)

The onset of diabetes, sickle-cell anemia, and malaria are all marked by a gradual stiffening of red blood cells. While devices and methods exist for sorting blood cells by size, those techniques are insensitive to other properties such as a cell’s stiffness. Now, Dmitry Fedosov and colleagues at the Jülich Research Center in Germany have used computer simulations to show how modifications to a microfluidic cell-sorting device could allow red blood cells to be sorted via their deformability. Such devices could allow clinicians to quickly and cheaply spot the onset of diseases that involve cell stiffening.

The investigated cell-sorting device normally consists of staggered rows of micrometer-sized circular posts that organize a flow of cells into different streams according to cell size. Fedosov’s team has shown that if the posts instead have sharp edges, then the device could separate cells into groups with differing stiffnesses. Their simulations show that a squishy red blood cell bends when it bumps into a diamond- or triangular-shaped post, and this bending causes the cell to hug the post and stay on course. In contrast, an unbending stiff cell bounces off any post it hits and is knocked into an adjacent stream. As the cells encounter successive rows of posts, they slowly fan out according to their stiffness. Simulations with circular posts show no such separation.

The team says that there are no major hurdles to making their proposed device, and other researchers have sorted cells experimentally using noncircular pillars. However, the team adds that the optimal experimental settings—such as cell flow rate—needed to sort cells with varying degrees of stiffness will require fine-tuning. While the team has so far simulated only red blood cells, the technique should work on any type of cell.

This research is published in Physical Review Fluids.

–Christopher Crockett

Christopher Crockett is a freelance writer based in Arlington, Virginia.


Features

More Features »

Announcements

More Announcements »

Subject Areas

Biological PhysicsMechanicsFluid Dynamics

Previous Synopsis

Particles and Fields

Neutrino Probes of Long-Range Interactions

Read More »

Next Synopsis

Related Articles

Synopsis: Fluid Dynamics Model for Cancer Patterns
Medical Physics

Synopsis: Fluid Dynamics Model for Cancer Patterns

Computer simulations indicate that friction and viscosity determine the patterns that cancerous cells form on skin tissue. Read More »

Synopsis: Air Jets Reduce Car Drag
Fluid Dynamics

Synopsis: Air Jets Reduce Car Drag

Wind tunnel experiments show how blasting air from the back of a vehicle can reshape the vehicle’s wake and lower its drag by several percent. Read More »

Synopsis: Two Nanodrops Zip Together to Form One  
Fluid Dynamics

Synopsis: Two Nanodrops Zip Together to Form One  

Simulations reveal that nanometer-scale droplets merge via a zipping-like action initiated by molecular-sized waves on their surfaces. Read More »

More Articles