Human Coagulation Factor VIIa PRODUCT INQUIRY Participation of Factor VIIa in the Extrinsic Factor Xase Complex The components of the extrinsic factor Xase enzyme complex are illustrated. Factor VIIa and its cofactor tissue factor (TF) assemble on a negatively charged membrane surface in a calcium dependent manner to form an enzyme complex which proteolytically converts factor X to factor Xa. The complex is referred to as the extrinsic factor Xase complex, because the tissue factor component is presumably derived from a source "extrinsic" to the plasma environment, which is accessible following vascular injury. HCVIIA-0031 Human Factor VIIa Pricing: Please Inquire SAMPLE DATA SHEET | SAFETY DATA SHEET Size 20 µg Formulation 50% glycerol/water (v/v) Storage -20°C Purity >95% by SDS-PAGE Activity Determination Factor VII clotting assay Shelf Life (properly stored) 12 months