coagulationrelated

Coagulation-related describes processes that cause a liquid to form a solid or semi-solid mass. In biology, this term is often used to refer to the hemostatic coagulation system that prevents excessive bleeding after vascular injury. In environmental and chemical contexts, coagulation refers to processes that destabilize suspensions so particles aggregate and settle, a key step in water and wastewater treatment.

Biological coagulation begins with vascular injury, where platelets adhere to damaged endothelium and release signals that promote further platelet activation. This leads to the activation of a series of plasma proteins, known as coagulation factors, organized into the intrinsic and extrinsic pathways. Both pathways converge on the common pathway, where thrombin is generated. Thrombin converts soluble fibrinogen into insoluble fibrin strands, forming a mesh that stabilizes the platelet plug into a clot. Factor XIII cross-links fibrin to strengthen the clot. The process is tightly regulated by anticoagulant proteins (such as antithrombin III and protein C/S) and by fibrinolysis, in which plasmin degrades fibrin to dissolve clots when healing occurs.

Disruptions in coagulation can cause bleeding disorders (for example, hemophilia A or B, and von Willebrand disease) or thrombotic conditions (such as deep vein thrombosis or pulmonary embolism). Diagnostic tests include prothrombin time (PT/INR), activated partial thromboplastin time (aPTT), platelet counts, and fibrinogen levels. Treatments range from anticoagulants and antiplatelet drugs to clotting factor concentrates and vitamin K depending on the underlying condition.

In water treatment, coagulation involves adding coagulants (like alum or ferric salts) to destabilize suspended particles, followed by flocculation to form larger aggregates that can be removed by sedimentation or filtration. The term thus spans medical, laboratory, and environmental applications.