Additional Information:

Samples should be collected from fasting patients. Morning samples are preferred, as iron values decrease by 30 percent during the course of the day.

CPT Code(s):


Specimen Requirements:

Type: Serum or plasma

Container/Tube: Serum gel or heparinized plasma

Sample Volume: Submit full tube

Minimum volume: 0.5 mL serum or plasma


  • Send specimens in their original tubes.
  • Centrifuge tubes if there is a delay in transport of more than 1 hour.

  • Samples are stable for up to 4 days at 15 – 25°C.
  • Samples are stable for up to 7 days at 2 – 8ºC.

Unacceptable Conditions: Samples with moderate or marked hemolysis will be rejected.

Specimen Retention Time: 5 days


Iron measurements are used in the diagnosis and treatment of diseases such as iron deficiency anemia, hemochromatosis and chronic renal disease.


This method utilizes TPTZ [2,4,6-Tri-(2-pyridyl)-5-triazine] as the chromogen.3 In an acidic medium, transferrin-bound iron dissociates into free ferric ions and apo-transferrin. Hydrochloric acid and sodium ascorbate reduce the ferric ions to the ferrous state. The ferrous ions then react with TPTZ to form a blue colored complex which can be measured bichromatically at 600/800 nm. The increase in absorbance is directly proportional to the amount of transferrin bound iron present. (Package Insert, OSR General Chemistry BAOSR6x86.03 2012-01 )


Within 24 hours

Reference Values:

Adults: 50-212 μg/dL