Calbiotech FT3 Elisa Kit - Triiodothyronine, Free

Product Description

PRINCIPLE OF THE TEST
The CBI fT3 is a solid phase competitive ELISA. The samples, and fT3 enzyme conjugate are added to the wells coatedwith anti-T3 monoclonal antibody. fT3 in the patient™s serum competes with T3 enzyme conjugate for binding sites inanti-T3 antibody. Unbound T3 and T3 enzyme conjugate is washed off by washing buffer. Upon the addition of thesubstrate, the intensity of color is inversely proportional to the concentration of fT3 in the samples. A standard curve isprepared relating color intensity to the concentration of the fT3. 

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 thecarrier proteins are altered in many clinical conditions, such as pregnancy. In normal thyroid function as theconcentrations of the carrier proteins alters, the total T3 level changes so that the freeT3 concentration remainsconstant. 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 totalT3 levels while the free T3 concentration remains basically unchanged.