Protein precipitation reaction - the salt analysis of protein.

The phenomenon of salt analysis refers to the decrease in the solubility of
proteins
in high-concentration salt solutions, so when neutral salts are added to their solutions to a certain concentration, the protein is precipitated from the solution. The role of salt analysis is related to two factors:
(1) the protein molecule is dehydrated by the strong salt, and
(2) the charge of the molecule is mediumed.of proteins is a reversible process, which causes less protein denaturation when precipitated by salt analysis methods and dissolves when diluted by dialysis or water.the neutral salt concentration required for different proteins in salt analysis is related to protein types and pH. Proteins with large molecular weights (e.g. globulins) are easier to come up with than globulins with smaller molecular weights (e.g. clear proteins). Globulin can be in the semi-saturated ammonium sulfate solution, while clear protein needs to be in the saturated ammonium sulfate solution to be able to be dissected.
Sodium chloride solution for egg whites (an egg clear plus 10 servings of 0.9% sodium chloride solution)
2.Solid ammonium sulfate
3.10% sodium hydroxide solution
4.1 % copper sulfate solution"Experimental operation" 1. Take the egg sodium chloride solution about 2 ml in
tum tube
, add ammonium sulfate powder, until ammonium sulfate saturation no longer dissolves, at this time the solution color is milky white, with
filter paper
filtration
. . 2. Take the filter to do a double-shrink reaction, check whether there is a protein in the filter.
protein precipitation is dissolved with 1 ml of distilled water and then double-shrink reaction, proving that the salt-based protein is re-dissolved in water without causing denaturation. .