Gel-barrier tube (send entire tube) preferred. Red-top tube or green-top (heparin) tube is acceptable if centrifuged within 45 minutes and the serum or plasma is removed and placed in a tightly-stoppered secondary tube.
Collection:
Separate serum or plasma from cells within 45 minutes of collection; avoid hemolysis. To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested.
