Purity >95%, by SDS-PAGE under reducing conditions and visualized by silver stain. MW (observed): 60 kDa, reducing conditions. MW (theoretical): 45 kDa. The Recombinant Mouse Serpin A1c/alpha-1-Antitrypsin Protein from R&D Systems is derived from NS0. The Recombinant Mouse Serpin A1c/alpha-1-Antitrypsin Protein has been validated for the following applications: Inhibition Activity.