Analyzing the effects of small channel width on cell concentration in blood flow

Understanding red blood cell and particle concentration distribution in the blood stream helps scientists analyze properties of our blood that play important roles in our circulatory systems, which can lead to medical application such as helping doctors predict blood clots and researchers develop more efficient drug delivery systems.

By employing novel techniques for microchannel fabrication and imaging analysis, Tatsumi et al. identified detailed properties of the concentration profile of particles and fixed red blood cells in blood flow.

The authors measured the density distribution of particles and red blood cells suspended in fluids flowing through a microchannel with an inner diameter of roughly 30 µm. They discovered that high concentration peaks of particles and cells tend to appear where collisions between the particles and cells occur, and the size of particles and the rotational motion of red blood cells also play a role. They also examined other factors that could affect the flow, including particle size effect, wall effects, streamwise location effect, and the hematocrit effect. They developed a numerical model to produce results comparable to the experimental measurements.

“To evaluate the concentration distribution of red blood cells in narrow blood vessels correctly, we need to understand the physics of how the particles and red blood cells migrate by the collision and what the difference between the motions of the particles and red blood cells could be,” Tatsumi said.

The authors intend on expanding this research by examining a mixture of particles with different diameters and increased channel size.

Source: “Particle and rigidized red blood cell concentration distributions in microchannel flows,” by Kazuya Tatsumi, Shinnosuke Noguchi, Akira Tatsumi, Reiko Kuriyama, and Kazuyoshi Nakabe, Physics of Fluids (2019). The article can be accessed at https://doi.org/10.1063/1.5111201 .