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Why is serum often used instead of plasma for chemical blood tests?
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blood analysis
The physical and chemical properties of a sample of blood are examined during blood analysis. The examination of blood is important for the accurate diagnosis of disease.
In the context of clinical blood analysis, serum is often preferred over plasma for chemical testing because it can be obtained from clotted blood without the addition of an anticoagulant.1
While plasma is the liquid portion of blood that remains when cells are separated, serum is specifically the fluid that remains after the blood has been allowed to coagulate. During this clotting process, the plasma protein fibrinogen is converted into fibrin, which forms a clot and is removed from the resulting liquid. By using serum, laboratories avoid the potential interference that anticoagulants might introduce during certain chemical procedures.231