What is the purpose of sodium citrate in the blood collection process?

Sodium citrate is primarily used in the blood collection process to prevent clotting. It functions as an anticoagulant by binding calcium ions in the blood. Calcium is necessary for various steps in the coagulation cascade; by sequestering these ions, sodium citrate effectively inhibits the coagulation process, allowing for accurate measurements in laboratory tests that require plasma, such as coagulation studies.

In the context of blood collection, this property is crucial because it ensures that the sample remains in a liquid state, allowing for proper analysis without interference from clot formation. This is particularly important for tests that assess blood clotting mechanisms or that require the measurement of certain components in plasma.

While other options might relate to various aspects of blood collection and storage, sodium citrate's defining role is specifically as an anticoagulant, making it essential for preventing clotting during sample collection and processing.