Mechanical Properties Measurement of Sickle Cell (SS) Red Blood Cells Using Optical Tweezers

Red blood cell deformability is a crucial factor in blood flow. Since sickle cell anemia is a disease characterized by a non-conforming deformation of red blood cells (RBCs) in oxygen-deprived conditions. This thread-like shape causes poor blood circulation. We measured, and compared, Sickle RBCs deformability by lateral indentation using optical tweezers. We used a camera to acquire the various videos. The trapped microbead distributions were processed using Boltzmann statistics to calculate the optical trap stiffness and trapping force. Finally, the Hertz model was used to determine the mechanical properties of sickle cell red blood cells. The mean values of shear modulus measured were (3.94 ± 0.71) µN/m for the sickle RBC Type I, (8.54 ± 1.7) µN/m for sickle RBC Type II and (11.72 ± 2.05) µN/m for sickle RBC Type III. These results confirmed that lateral indentation is becoming an almost indispensable technique for characterizing red blood cells.