Cohn—Edsall equation

The basis for characterizing fractionated precipitation of proteins is the Cohn-Edsall equation (Cohn, 1943) [Eq. (8.60), where S is the solubility of the protein, is the solubility in salt-free solution, Ks is the salting-out constant, and I represents the ionic strength]. 

Building Quantitative Models for the Hofmeister Series and Cohn-Edsall and Setschenow Equations... 

While the Hofmeister series and the Cohn-Edsall and Setschenow equations are useful tools for the estimation of protein stability and precipitation behavior, their usefulness is limited because of the lack of a quantitative relationship to molecular or solution properties. The goal of past and current efforts is to quantify the Hofmeister series and to predict the constants Ks and /3 (or Ks and log [E]0) in the Cohn-Edsall or Setschenow equations, respectively. Some of the most relevant efforts focus on ... 

A stig — dielectric increment per gm. protein per liter /r = dipole moment in debye units t H O is the relaxation time in water at 25° (correcting for the relative viscosity of water and the solvent actually employed) To = relaxation time of a sphere, of volume equal to that of the protein, in water at 25° ajb = ratio of major to minor axis, calculated from r and observed relaxation times, by the equations of Perrin (92) [Cohn and Edsall (Jd)], neglecting hydration. 

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