Читать книгу Fundamentals of Analytical Toxicology - Robin Whelpton - Страница 41

When whole blood is allowed to stand (15 min, room temperature) in a plain tube (no anticoagulant) a clot normally forms that will retract sufficiently to allow serum to be collected after centrifugation. For many analyses, serum is preferred to plasma because it produces less precipitate (of fibrin) on freezing and thawing.