Serum-separating tubes, also known as serum separator tubes or SSTs, are test tubes used in clinical chemistry tests requiring blood serum.
SSTs are sometimes called "gold-topped tubes", "tiger-tops", or "marble-top tubes", referring to the stoppers which are either gold, red with a gold ring on top, or marbled red and grey. The stopper of SPS (sodium polyanethol sulfonate) tubes have a paler yellow color, sometimes causing confusion; these are known as "yellow tops" not "gold". Trademarked versions of the SST include Covidien "Corvac" tubes.
Features
editThe tubes have micronized silica particles which help clot the blood before centrifugation, and a gel at the bottom which separates whole blood cells from serum.[1] Silica nanoparticles induce coagulation through contact activation of coagulation factor XII (Hageman factor).[2] The silica particles are desiccants, which adsorb and hold water vapor.[3] This is used in the tubes so the blood adheres to the surface of the tiny silica particles and begins to clot. After the blood sample is centrifuged, the clear serum should be removed for testing.[4][5]
Use
editThese tubes should be used with care when measuring drug or hormone levels because the drug or hormone may diffuse from the serum into the gel, causing a reduction in measured level. The gel in SST II tubes (which appears slightly less opaque) is supposed [weasel words] to have less effect on drug levels in serum. [citation needed]
Blood samples should be allowed time to form a clot at room temperature for 30–60 min.[6]
CDC recommends a range of time to allow clot formation that was reasonably consistent, from a minimum of 30 min to 60 min maximum.[7]
See also
editReferences
edit- ^ "Greiner Bio-One VACUETTE Z Serum Sep Clot Activator Tubes - Non-ridged (pull cap)". Blood, Hematology and Coagulation Testing Products, Blood Specimen Collection. Thermo Fisher Scientific Inc. Retrieved 2022-12-16.
- ^ Ilinskaya AN, Dobrovolskaia MA (June 2013). "Nanoparticles and the blood coagulation system. Part II: safety concerns". Nanomedicine. 8 (6): 969–981. doi:10.2217/nnm.13.49. PMC 3939602. PMID 23730696.
- ^ Vogelbaun L (14 March 2014). "How Does Silica Gel Work?". BrainStuff - HowStuffWorks. YouTube. Retrieved 2022-12-16.
- ^ Mitchell B, Neary M, Kelly G (2003). "Blood sampling in sheep" (PDF). Purdue University Cooperative Extension Service. Archived from the original (PDF) on 2007-02-03.
- ^ Thavasu PW, Longhurst S, Joel SP, Slevin ML, Balkwill FR (August 1992). "Measuring cytokine levels in blood. Importance of anticoagulants, processing, and storage conditions". Journal of Immunological Methods. 153 (1–2): 115–124. doi:10.1016/0022-1759(92)90313-i. PMID 1381403.
- ^ Tuck MK, Chan DW, Chia D, Godwin AK, Grizzle WE, Krueger KE, et al. (January 2009). "Standard operating procedures for serum and plasma collection: early detection research network consensus statement standard operating procedure integration working group". Journal of Proteome Research. 8 (1): 113–117. doi:10.1021/pr800545q. PMC 2655764. PMID 19072545.
- ^ "Collecting, Preparing, and Shipping Serum Specimens to CDC for Serology Testing" (PDF). U.S. Centers for Disease Control and Prevention.