Feasibility study of a sinusoidal shear flow generator for using counter-oscillating flow fields in monitoring of individual red blood cells under shear flow conditions

Aim: To develop a prototype device that allows direct observation of the deformation of individual red blood cells (RBCs) in an oscillating shear flow field. Method: A counter-oscillation mechanism composed of two parallel glass plates was constructed to keep RBCs floating at the centerline of a 30 μm fluid gap. RBCs in the suspension fluid were observed using a high-speed camera with 40-fold magnification. Results: RBCs remained within the camera’s field of view when exposed to a shear force field that oscillated at 2 Hz. Moreover, glutaraldehyde-treated, hardened RBCs always tumbled and low-density RBCs had a larger elongation than high-density RBCs when exposed to the same shear field. Conclusion: The feasibility of this counter-oscillating mechanism for evaluating RBC deformability has been demonstrated.