Stationary deformations of erythrocytes by high-frequency electric field

The theory of erythrocyte deformation by high-frequency (HF) electric field, based on ellipsoidal approximation for cell shape, is developed. Various possible deformational regimes of cell elongation by the field are analyzed, depending on the relation between the bending and the shear deformations of cell membrane and the magnitudes of corresponding mechanical stresses arising. The role of mechanical, electrical, and geometrical parameters of erythrocyte in formation of various parts of deformational curves (cell length-field strength) is elucidated, including the initial part and the geometrical saturation region. The measurements of the stationary elongation curves of erythrocytes by Krueger and Thom [Biophys. J. 73 (1997) 2653] are analyzed quantitatively. The shape of the measured curves is described exactly by the theory for the whole range of field strengths and temperatures used. The temperature-dependent values of erythrocyte volume and cytoplasmic conductivity are obtained from this description in the range (- 15-25 degrees C).