1, salt precipitation method:

Salt precipitation method is based on the protein in dilute salt solution, solubility will rise with the increase in salt concentration, but when the salt concentration increases to a certain value, so that the water activity decreases, which leads to the protein molecule surface charge is gradually neutralized, hydration membrane gradually destroyed, and ultimately cause the protein molecules coalesce with each other and precipitate from the solution.

2, organic solvent precipitation:

Organic solvents can reduce the solubility of proteins for two reasons: first, with the same salt solution has a dehydrating effect; second, the dielectric constant of organic solvents is smaller than that of water, resulting in the solvent's polarity is reduced.

3, protein precipitant:

Protein precipitant only a class or a protein precipitation role, common alkaline proteins, lectins and heavy metals.

4, polyethylene glycol precipitation:

Polyethylene glycol and dextran sulfate sodium and other water-soluble nonionic polymers can make protein precipitation.

Expanded information:

Adsorption Chromatography

1, Adsorption Column Chromatography

Adsorption Column Chromatography is a method that uses a solid adsorbent as the Solid adsorbent as a stationary phase, organic solvent or buffer as the mobile phase to form a column of a chromatographic method.

2, thin-layer chromatography

Thin-layer chromatography is a chromatographic method with the substrate coated on the carrier such as glass plate or polyester sheet as stationary phase and liquid as mobile phase. In this chromatographic method, a substance such as an adsorbent is coated on a carrier to form a thin layer, and then the layer is spread according to the paper chromatography operation.

3, polyamide film chromatography

Polyamide adsorption of polar substances is due to its ability to be separated from the formation of hydrogen bonds between the material. The strength of this hydrogen bond determines the size of the adsorption capacity between the separated material and the polyamide film.

During chromatography, the spreading agent competes with the separates to form hydrogen bonds on the surface of the polyamide film. Therefore, choosing the appropriate spreading agent to make the separation on the surface of the polyamide membrane adsorption, desorption, re-adsorption, and then desorption of the continuous process can lead to the separation of the separation of substances to achieve the purpose of separation.