Gold serum separator (SST) tube
Spin
Red serum vial/tube, 5 mL
Transfer vial/tube with cap - 12mL (LabCorp)
Ambient (preferred) - 7 days
Refrigerated - 14 days
Frozen - 2 months
Cell culture-based radioimmunoassay (RIA)
Negative: 0.00 - 0.24 nmol/L