An estimate of red cell membrane strain is applied to the case of a dilute suspension of osmotically inflated near spherical red cells subjected to shear. The wall shear stress is related to maximum membrane strain, and predictions of theory arc compared to experimental results on hemolysis of Champion et al. (Biorheology, 8 (1971), 23). It appears membrane strain energy at hemolysis is a function of the ratio of cell to suspending fluid viscosity, so long as membrane properties are unaltered by the nature of the suspending fluid. This is seen to bc in agreement with Taylor’s (Proc. R. Soc. Lond. Ser. A. 146 (1934), 501) results on the hurst of liquid drops. An attempt is made to compare the conditions for hemolysis obtaining in steady shear flow with those of oscillatory shear. The analytical results appear to be consistent with reported observations concerning the time dependent nature of hemolysis.
