The equilibrium configuration of the soft shell preserving the surface area as applied to the biomechanics of the erythrocyte

Article

Published: 20.10.2025

Authors: Sorokin F.D., Banin E.P., Ganeeva A.R.

Published in issue: #11(167)/2025

DOI:

Category: Mechanics | Chapter: Biomechanics and Bioengineering

The paper shows that a soft shell that preserves the surface area, when loaded with internal pressure, always takes the shape of a sphere, regardless of the initial configuration. That is why red blood cells under the influence of osmotic pressure always look like spheres in the images, and not like ellipsoids. If, in addition to internal pressure, an axial force is applied to a soft shell that preserves the surface area, then the configurations of such a shell become much more diverse. You can apply axial force to the red blood cell with optical tweezers or two pipettes, as well as squeeze the red blood cell with flat plates. The configurations of such shells under various combinations of pressure and axial force are investigated.

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