How does EDTA function as an anticoagulant?

EDTA, or ethylenediaminetetraacetic acid, functions as an anticoagulant primarily by chelating calcium ions in the blood. Calcium is essential for various steps in the blood coagulation process, specifically in the activation of several clotting factors that are crucial for forming clots. By binding to calcium, EDTA effectively removes it from circulation, thereby disrupting the coagulation cascade and preventing the formation of blood clots.

This mechanism is particularly useful in laboratory settings, where the prevention of coagulation is necessary for accurate blood tests and analyses. Since calcium is key to both the intrinsic and extrinsic pathways of the coagulation cascade, its chelation leads to an effective inhibition of clot formation.