Affiliations: [a] Department of Physics, Faculty of General Studies, Gunma University, Maebashi 371, Japan | [b] Department of Polymer Science, Faculty of Technology, Gunma University, Kiryu 376, Japan
Note: [] Accepted by: Editor S. Oka
Abstract: In order to consider the effect of membrane fluidity upon the mechanical property of biological cell suspensions, we have calculated the complex intrinsic viscosity [η∗]=[η′]−i[η″] of spherical shell structures with material incompressibility in suspension as a function of the dimensionless frequency x=ωη′a/γ′ together with the parameters of hm=ηm/η′, g=γ/γ′, h=η/η′, δ=d/a, where a is the radius of the cell, d is the width of the membrane, η, ηm, and η′ are the viscosities of the medium, of the membrane and of the internal region of the cell, γ and γ′ the surface tensions at the outer and the inner side of the membrane respectively, and w the angular frequency. The result is simply represented by two dispersions as follows: [η∗]/[η]=A1+B1/(1+iωτ1)+B2/(1+iωτ2). Here i is the imaginary unit, A1=2(1−h)/(2+3h)+O(δ), B1=3h/(5+5h)+O(δ), B2=h(19+16h)/{5(1+h)(2+3h)}+O(δ), τ1={(5/24)(1+h)(1+1/g)δ−2+O(δ−1)}aη′/γ′, τ2=[(2+3h)(19+16h)/40(1+h)(1+g)+O(δ)]aη′/γ′ and [η]=(5/2){96hmg+32g(5+5h−12hm)δ+O(δ2)}/{96hmg+32g(5+2h−12hm)δ+O(δ2)}.
