The influence of red cell size relative to pore size on filtration through nuclepore filters.

A simple model relating pore passage time (PPT) to the degree of strain of the membrane of a red cell of diameter DC on passing through a pore (diameter Dp) has been developed. The model was tested for a range of mammalian and fish species for which some data was available for more than one pore size. The strain (epsilon) is estimated as (Dc-Dp)/Dc. For small epsilon, less than approximately 0.45, PPT was small but rose rapidly for higher values. The analysis provides a simple basis for choosing appropriate pore sizes, and consequently strain, for comparing mechanical properties of erythrocytes of different species.