Ammonium sulfate precipitation

Ammonium sulfate precipitation is one of the most commonly used methods for large and laboratory scale protein purification and fractionation that can be used to separate proteins by altering their solubility in the presence of a high salt concentration. == Properties == Ammonium sulfate is an inorganic salt with a high solubility that disassociates into ammonium (NH+4) and sulfate (SO2−4) in aqueous solutions.

Source: Wikipedia — Ammonium sulfate precipitation (CC BY-SA 4.0)