Calbiotech Free Triiodothyronine (FT3) ELISA

SUMMARY AND EXPLANATION 
Over 99% of Triiodothyronine (T3) circulates in blood is bound to carrier proteins; thyroxine-binding globulin (TBG). However, only the free (unbound) portion of T3 is responsible for the biological action. Further, the concentrations of the carrier proteins are altered in many clinical conditions, such as pregnancy. In normal thyroid function as the concentrations of the carrier proteins alters, the total T3 level changes so that the freeT3 concentration remains constant. Thus, measurements of free T3 concentrations correlate more reliably with clinical status than total T3 levels. The increase in total T3 levels associated with pregnancy, oral contraceptives and estrogen therapy result in higher total T3 levels while the free T3 concentration remains basically unchanged.

PRINCIPLE OF THE TEST 
The CBI FT3 is a solid phase competitive ELISA. The samples, and FT3 enzyme conjugate are added to the wells coated with anti-T3 monoclonal antibody. FT3 in the patient’s serum competes with T3 enzyme conjugate for binding sites in anti-T3 antibody. Unbound T3 and T3 enzyme conjugate is washed off by washing buffer. Upon the addition of the substrate, the intensity of color is inversely proportional to the concentration of FT3 in the samples. A standard curve is prepared relating color intensity to the concentration of the FT3.

STORAGE AND STABILITY 
1. Store the kit at 2 – 8°C. 
2. Keep microwells sealed in a dry bag with desiccants. 
3. The reagents are stable until expiration of the kit. 
4. Do not expose test reagents to heat, sun, or strong light.