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HelpTest Code LAB1916 T4 Free
Performing Section
Chemistry
Purpose/Principle
For the quantitative determination of Free Thyroxine (FT4) in serum and plasma
Special Collection Notes
Collect specimen according to standard operating procedure.
Specimen Type
Serum/Plasma:
Light Green Tube Top-Lithium Heparin (Preferred)
Gold Top Tube-SST
Red Top Tube-Plain
Specimen Volume
Preferred: 1.5 mL
Minimum: 0.6 mL (0.3 mL Serum/Plasma)
Processing Instructions
Allow sample to clot in upright position for 30 minutes.
CENTRIFUGE sample per procedure.
Store and send sample refrigerated via courier.
Temperature
Refrigerated
Test Components
Free T4 (Free Thyroxine)
Reference Range
0 up to 3 Days: 2.00-5.00 ng/dL
3 Days up to 1 Month: 0.90-2.20 ng/dL
1 Month up to 19 Years: 0.80-2.00 ng/dL
19 Years and up: 0.78-2.19 ng/dL
TAT
Routine: 120 Minutes
STAT: 60 Minutes
Sample Stability
Ambient: Not recommended
Refrigerated: 6 days
Aliases
FT4
T4F
Free Thyroxine
CPT
84439
Test/Batch Schedule
Runs daily-on demand
Method
Chemiluminescent microparticle immunoassay (CMIA)