Shear viscoelasticity of suspensions of biological cells with viscoelastic membrane

To discuss the relaxation phenomena of biological cell suspensions, we have calculated the complex intrinsic viscosity of the dispersion of spherical cells with a viscoelastic membrane as a function of the frequency taking account of interfacial tension at both the interfaces of the membrane. The Voigt model is used to describe the viscoelasticity of the cell membrane. In general it is possible for four relaxations to exist. Under a finite membrane viscosity it is predicted that there exist two relaxations. The amplitude of relaxation for the shorter relaxation time is larger than that for the longer relaxation time. The results are compared with the experimental ones.