Sodium Pyrophosphate is a potent serine-threonine phosphatase inhibitor that is commonly used in kinase reaction buffers. It is often used in combination with other phosphatase/protease inhibitors for broad spectrum inhibition. Sodium Pyrophosphate is soluble in water (65 mg/ml) and a typical working concentration used is 1 to 100 mM. This phosphatase inhibitor can be combined with lysis and extraction buffers to support downstream purification procedures.