Question

Why is sodium chloride not generally used for the fractional precipitation of proteins

Answer 1

A:-

Fractional precipitation of Proteins:
                                    High concentrations of salts promote precipitation of proteinns. With increasing ionic strength od salts proteins begin to interact via hydrophobic parts on their surface as proteins and salt compete for the residual water.Generally ammoniumsulfate, (NH4)2SO4 is used as the best salt for frational precipitation of proteins. Ammonium sulfate preserves protein activity and promotes precipitation at lower concentrations than other salts. Sodium chloride and many potassium salts are not sufficiently soluble and many multivalent cations are toxic. So sodium chloride is not suitable for fractional precipitation of proteins.