Free T3 ELISA Kit

Name Free T3 ELISA Test
Full name Human Free T3 ELISA Test Kit
Category Name Thyroid ELISA kits
Test 96
Method ELISA: Enzyme Linked Immunosorbent Assay
Principle Competitive ELISA
Detection Range 0-24pg/mL
Sample 50µL
Sensitivity 0.05pg/mL
Total Time ~60min
Shelf Life 12Months from the manufacturing date

Free T3 ELISA kit description:

The Diagnostic Automation Inc. free T3 ELISA kit test is an Enzyme Linked Immunosorbent Assay which can be used to determine the levels of Free T3 in human serum samples.

Materials provided with Free T3 ELISA Test Kit:

1. Anti-T3 Antibody-coated ELISA Microplate (96 wells)

2. enzyme conjugate reagent: 1 Vials contains T3-HRP with preservative buffer, ready to use.(1 Vials, 12 ml)

3. standard set, contains 0, 1.5, 3, 6, 12, 24 pg/mL ,ready for use. (6 vials. 1 ml)

4. TMB Substrate: Hydrogen peroxide and tetra-methyl benzidine in preservative buffer, ready to use. (1 vial of 11ml)

5. Stop Solution: a normal hydrochloric acid (1 vial, 6 ml).

6. Concentrated washing buffer: PBS-Tween (1 vial 30ml) (20X)

7. Control serum: Free T3 in serum with preservatives(1Vial, 1 ml)

Materials Required, not Provided:

1. Precision pipettes(20,50,100, µl)

2. Distilled or deionized water

3. EIA kit Microplate Washer

4. EIA kit Microplate Reader with a 450 nm, If possible, 630 nm as reference.

5. Absorbent paper


3,5,3′ triiodothyronine (T3) hormone secreted by thyroid gland and circulates in the bloodstream, mostly bound to the plasma proteins, thyroxine binding globulin (TBG), prealbumin and albumin. The remaining is free T3, unbound and its metabolic potency is much greater. A free T3 concentration measurement is an important factor in diagnosis of thyroid diseases. Total T3 concentration determination to identify hyperthyroidism cases with normal T4 and increased concentration of T3 is important. Total T3 Increase with no increasing in T4 often represents recurrence of hyperthyroidism in earlier treated patients. T3 hormone regulates cell metabolism and body growth and its level is good indicator of thyroid disease state and body metabolism. Alteration of plasma proteins in clinical conditions such as pregnancy and drugs usage like contraceptive pills, estrogen therapy, phenytoins, androgens lead to falsely increase in total T3 but not in free T3 level. Therefore assessing the FT3 is a reliable diagnostic tool for estimation of thyroid disease.

Principle of the assay

This ELISA test is based on the use of specific monoclonal antibody against a distinct antigenic determinant on the intact T3 molecule. Anti- T3 monoclonal antibody with a certain concentration is used for coating the wells. A certain amount of serum and enzyme conjugate containing the bounded T3 to HRP-T3 enzyme. In the incubation period, the present free T3 and T3-HRP in serum, compete for binding to the coated Anti-T3 monoclonal antibody in wells; after 45-minute incubation at room temperature, the well is washed with washing solution. Then substrate solution and chromogen solution are added and incubated for 15 minutes, resulting in the development of blue color. The color development is stopped with the addition of stop solution, and the resulting yellow color is measured spectrophotometrically at 450 nm. The concentration of Free T3 is inversely proportional to the color intensity of the test sample.