Used in research and diagnostic applications to detect and quantify Factor XI, a key protein in the intrinsic coagulation pathway. Helps in studying blood clotting disorders and evaluating the efficacy of anticoagulant therapies. Employed in immunoassays to measure Factor XI levels in plasma, supporting the development of treatments for thrombotic diseases. Also utilized in neutralization studies to inhibit Factor XI activity in vitro, aiding in the understanding of its role in hemostasis and thrombosis.