Human Coagulation Factor XIa PRODUCT INQUIRY Proteolytic Activation of Factor XI The activation of factor XI by factor XIIa is illustrated. Although factor XI can bind independently to negatively charged surfaces, proteolysis by factor XIIa can only occur in the presence of surface- bound high molecular weight kininogen (HMWKa). The bound HMWKa is susceptible to proteolysis by the newly generated factor XIa which results in a loss of its biological activity (HMWKi). Factor XIa catalyzes the proteolytic conversion of factor IX to factor IXa either in solution phase or when bound to a negatively charged surface. HCXIA-0160 Human Factor XIa Pricing: Please Inquire SAMPLE DATA SHEET | SAFETY DATA SHEET Size 50 µg Formulation 50% glycerol/water (v/v) Storage -20°C Purity >95% by SDS-PAGE Activity Determination Factor XI clotting assay Shelf Life (properly stored) 12 months