A Method for Deproteinization of Blood and Other Body Fluids

Deproteinization is a necessary step in many procedures for the chemical analysis of body fluids. A variety of reagents have been used for this purpose, especially in blood analysis. Of these perhaps tungstic acid and trichloracetic acid are the most widely used to-day, and for this reason we may consider them a moment. Folin and Wu (1919) introduced tungstic acid to prepare protein-free filtrates for their system of blood analysis. In this method it is usual to employ 667 m.Eq. of the acid to precipitate the proteins from a litre of plasma or whole blood and twice this concentra-tion to deproteinize the same volume of packed erythrocytes. With the use of sodium tungstate and sulphuric acid equivalent amounts of Na and