Available online at www.sciencedirect.com ScienceDirect Comput. Methods Appl. Mech. Engrg. 325 (2017) 22–36 www.elsevier.com/locate/cma Atomistic–continuum model for probing the biomechanical properties of human erythrocyte membrane under extreme conditions A.S. Ademiloye a , L.W. Zhang b, ∗ , K.M. Liew a , ∗ a Department of Architecture and Civil Engineering, City University of Hong Kong, Kowloon, Hong Kong, China b School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai 200240, China Received 19 March 2017; received in revised form 24 June 2017; accepted 24 June 2017 Available online 13 July 2017 Abstract A precise first attempt is performed to quantify the biomechanical properties of human erythrocyte membrane subjects to extreme temperature and loading conditions. An improved three-dimensional (3D) atomistic–continuum model based on the Cauchy–Born rule is proposed to investigate the elastic properties and biomechanical responses of the erythrocyte membrane. A membrane rigidity model is developed to estimate the membrane elastic properties over an extreme temperature range. Our computational results reveal that the membrane is able to sustain large strains up to a certain limit; beyond which, mechanically induced hemolysis may occur as exponential stress increment, fluctuations and multiple peaks were observed in the stress–strain curves. Additionally, we found that the overall deformability of the erythrocyte membrane significantly decreases as temperature increases. It is concluded that the observed increase in membrane rigidity may be attributed to the denaturation, structural remodeling and cross-linking of membrane cytoskeletal proteins. c ⃝ 2017 Elsevier B.V. All rights reserved. Keywords: Erythrocyte membrane deformability; Large strains and deformation; Multiscale Cauchy–Born framework; Elastic properties; Temperature effect 1. Introduction The ability of erythrocytes or red blood cells (RBCs) to undergo a wide range of deformations while traversing vessels during microcirculation is crucial to the sustenance of life. Erythrocytes are undoubtedly a very important component of human blood, as they account for approximately 99% of the particulate matter in the blood and occupy between 40% and 45% of blood volume. This suggests that the properties and states of the cells determine the overall behavior of the blood. Some recent studies have also concluded that the development and progression of some blood- related hereditary diseases—such as sickle cell anemia, spherocytosis and elliptocytosis, and non-hereditary diseases ∗ Corresponding authors. E-mail addresses: zlvwen@hotmail.com (L.W. Zhang), kmliew@cityu.edu.hk (K.M. Liew). http://dx.doi.org/10.1016/j.cma.2017.06.033 0045-7825/ c ⃝ 2017 Elsevier B.V. All rights reserved.