One 7.5 mL serum separator tube (SST). Also acceptable: One 4 mL green top tube (sodium or lithium heparin) or one 4.5 mL plasma separator tube (PST). Do not draw from a limb receiving an intravenous infusion.
Handling:
Allow to clot, centrifuge SST or PST within 2 hours of collection and transport in original tube. Centrifuge green top tube and separate plasma into a plastic vial for transport. Refrigerate.