Protease inhibitors function by either reversibly or irreversibly inactivating the protease found in cell lysates. They achieve this by binding to the active site or modifying the protease's structure. These processes prevent protein sample hydrolysis, extending the storage duration without degradation. However, because no single chemical can effectively block all proteases, researchers often opt for ready-made cocktails or create custom mixtures of multiple inhibitor compounds to prevent proteolysis and maintain protein extract integrity.