Abstract

The effect of variation in temperature on the rheological properties of human red blood cells was studied by determining the cell deformation in response to aspiration pressure applied via a micropipette. The time history of the deformation was analyzed by the use of a Voigt viscoelastic model consisting of an elastic element (E) in parallel with a viscous element (eta). Viscosity values were obtained during the initial rapid deformation phase (phase I), the later slow deformation phase (phase II), and the recovery phase. With a rise in temperature from 0 to 45 degrees C, both E and eta values decreased. A thermotropic transition temperature was found at approximately 21 degrees C for phase I viscosity and at approximately 9 degrees C for viscosity in the recovery phase, but not for phase II viscosity. These responses to temperature variations provide insights into the viscoelastic properties of the erythrocyte membrane.