Numerical modeling of biomechanical responses of healthy red blood cell membrane under various loading conditions using a 3D quasicontinuum approach

With the rapid increase in the number of deaths worldwide due to blood related diseases such as malaria, sickle cell anemia and other types of anemias, the importance of more insightful studies on healthy red blood cell (RBC) membrane cannot be overemphasized since the development and progression of these infectious diseases are closely related to the state of the membrane. Furthermore, due to the recent increase in life-shortening terminal diseases leading to organ failure, the use and design of artificial organs must be enhanced and improved through a better understanding of the RBC membrane biomechanical properties to prevent hemolysis. In this paper, we modeled the biomechanical responses of healthy red blood cell (RBC) membrane under axial, shearing and area dilating loading conditions using a three-dimensional (3D) quasicontinuum approach. Here, the atomic scale strain energy density of the RBC membrane, computed using a representative unit cell of the spectrin cytoskeleton, is introduced into the continuum-scale for numerical simulation using the standard Cauchy-Born rule. Results obtained from this study confirm that the RBC membrane exhibit strong strain-stiffening behavior that is highly sensitive to microstructural changes as shown in its stress-strain relationship curves. We conclude that the RBC membrane can only sustain large strains up to a certain limit beyond which hemolysis may occur, hence strains and pumping forces in artificial blood-pumping devices must be precisely regulated.