آمونیوم سولفات

Ammonium sulfate ((NH₄)₂SO₄) is an inorganic salt widely used in biochemistry and molecular biology for protein purification by precipitation. It is a white crystalline solid, highly soluble in water, and works by reducing protein solubility (“salting out”) based on ionic strength.

🏭⚗️ Production

Ammonium sulfate is industrially produced by reacting ammonia with sulfuric acid. It is available commercially as a white powder and is commonly prepared as a saturated aqueous solution to add gradually during protein precipitation procedures.

🔬 Properties

Ammonium sulfate has a high solubility in water (about 70.6 g per 100 mL at 0 °C), and dissociates into ammonium (NH₄⁺) and sulfate (SO₄²⁻) ions. It increases ionic strength of solutions and promotes protein aggregation by reducing hydration shells around proteins. The process is reversible, allowing proteins to be redissolved after precipitation.

🧪 Applications

• Protein purification: Used for fractional precipitation to selectively precipitate proteins based on their solubility differences.
• Enzyme studies: Helps concentrate enzymes while maintaining activity.
• Biochemistry research: Commonly used in crystallization, storage, and stabilization of proteins.
• Industrial use: Applied in fertilizer production and food industry as a food additive.