Estradiol, Free (Includes Estradiol Total)
Collect 3mL serum from plain red top or SST. Serum must be separated from cells within 45 minutes of collection. If collected in plain red top, pour off serum into plastic transport tube, and indicate tube type on specimen.
Liquid chromatography tandem mass spectrometry (LC/MS/MS); equilibrium dialysis
Room temp 1 day, Refrigerated 6 days, Frozen 32 days