serum separator tube

Medical term Routine Blood Collections

Gold or red-gray (tiger) top. Its clot activator speeds clotting; when the tube is spun, its gel moves to sit between serum and cells as a barrier.

Sources

• WHO Guidelines on Drawing Blood: Best Practices in Phlebotomy (2010); official WHO IRIS PDF, also published as NCBI Bookshelf NBK138650 · World Health Organization
• Ford RB, Mazzaferro EM. Laboratory Diagnosis and Test Protocols, Table 5-1 Venous Blood Collection Tube Guide (reproduced from the BD Vacutainer Tube Guide). In: Kirk & Bistner's Handbook of Veterinary Procedures and Emergency Treatment, 2012 · Elsevier (via PubMed Central)
• Order of Blood Draw Tubes and Additives (CLSI blog summary of GP41, Collection of Diagnostic Venous Blood Specimens; GP41-Ed7 was replaced by CLSI PRE02-Ed8, 2025) · Clinical and Laboratory Standards Institute
• Nikolac N, Supak-Smolcic V, Simundic AM, Celap I. Croatian Society of Medical Biochemistry and Laboratory Medicine: national recommendations for venous blood sampling (based on CLSI H3-A6). Biochem Med 2013;23(3):242-254 (PMC3900082) · Biochemia Medica via PubMed Central

Related terms

• clot activatorAdditive that makes blood clot faster so serum can be obtained; carried over into a citrate tube, it can…
• serumThe liquid left after blood clots and is centrifuged; it lacks the clotting factors used up in the clot…
• refluxBackflow of tube contents into the vein; keeping the arm angled downward while tubes fill prevents it.
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• rolling veinA vein that slides away from the needle; anchoring the skin taut below the site holds it in place.
• sclerosed veinA hardened, cordlike vein, often from damage or clotting; it does not spring back when pressed and is not…
• small-volume tubeStandard-size tube with a weaker vacuum that draws less blood; used for children and fragile veins to reduce…
• sodium citrateAnticoagulant that binds calcium, used in light blue-top tubes for coagulation tests. Fill to the line to…
• sphygmomanometerA blood pressure cuff with a gauge. It can serve as a tourniquet when inflated to just below the patient's…
• syncopeFainting: brief loss of consciousness when too little blood reaches the brain. If it starts during a draw…

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