RANJINI BANDYOPADHYAY* and A K SOOD

Department of Physics, Indian Institute of Science,  Bangalore 560 012, India
* Present address: Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, CA 90095-1547, USA

 Abstract.

We study the rheology of semi-dilute solutions of the sodium salt of calf-thymus DNA in the linear and nonlinear regimes. The frequency response data can be fitted very well to the hybrid model with two dominant relaxation times t₀and t₁.~The ratio (t₀/t₁) ~ 5 is seen to be fairly constant on changing the temperature from 20 to 30^o C. The shear rate dependence of   viscosity can be fitted to the Carreau model.

Keywords:  DNA; rheology; hybrid model.

Pacs Nos.  87.15.He; 83.50.Fc; 83.50.Gd