What method used to prevent blood in the antigoaculant tubes from clotting?

Anticoagulants

- EDTA (Ethylenediaminetetraacetic acid): Binds calcium ions (Ca+2) which are essential for the activation of the clotting cascade preventing the conversion of prothrombin into thrombin

- Sodium Citrate: Forms an inactive complex with the calcium ions

- Heparin: Binds antithrombin, enhancing its inhibitory effect on thrombin and hence, the conversion of fibrinogen to fibrin

- Oxalate : Binds and removes the calcium ions

- Sodium Fluoride; Inhibits glycolysis, preventing bacterial growth.