How to Measure Cellular Shear Modulus Inside a Chip: Detailed Correspondence to the Fluid-Structure Coupling Analysis

Deformability of a red blood cell (RBC) is not only a required property for microcirculation but also an important indicator for pathological changes, which can be used for potential diagnoses of various diseases such as sepsis and vascular diseases. To date, various types of microfluidic platforms have been intensively developed for high-throughput measurements of RBC stiffness. This paper reports a novel strategy to measure the shear modulus of a RBC using on-chip feedback manipulation combined with a computational analysis of shape deformation. Here, we compared the shear deformations of a RBC flowing in a microchannel to that modeled in fluid-structure coupled simulation. The strain-velocity relationships for different values of shear modulus Gs obtained in both the experiments and simulation provide the direct correspondence of experimentally observable parameters (effective strain ε, velocity v) to a defined material constant Gs.