• Assay Type Competitive ELISA
  • Sample Types Urine, Tissue Culture Media, Extracted Serum, Plasma, and Fecal Extracts
  • Sensitivity 37.4 pg/mL
  • Species T3 is identical across species
  • Assay Duration 2.5 Hours
  • Samples/Plate 39 in Duplicate
  • Readout Colorimetric, 450 nm
  • Standard Curve Triiodothyronine (T3) ELISA Kit
  • Description

    Assay Principle: 

    The Triiodothyronine (T3) ELISA Kit quantitatively measures T3 in urine, tissue culture media, extracted serum, plasma, and fecal extracts. The Triiodothyronine (T3) ELISA Kit is a competitive ELISA with a run time of 2.5 hours. Please read the complete kit insert for more information before performing this assay.

    Use our provided T3 standard to generate a standard curve for the assay. Pipette the standards or diluted samples into a transparent microtiter plate coated with our donkey anti-sheep IgG antibody. Add the T3 peroxidase conjugate and the T3 sheep antibody. Then incubate the mixture covered at room temperature, shaking for 2 hours. The immunological reaction occurs between the anti-T3 antibody, the T3 antigen in the sample or standard, and the T3-peroxidase conjugate. As the T3 concentration in the sample increases, the bound T3-peroxidase conjugate decreases, causing a decrease in signal and vice versa. 

    After the 2-hour incubation, wash away the excess T3-peroxidase conjugate and add the TMB substrate. The TMB substrate reacts with the bound T3-peroxidase conjugate generating a signal detected by a plate reader at 450nm. Use the intensity and the standard curve to calculate the T3 concentration in the samples.


    Triiodothyronine, also known as T3, is a thyroid hormone. Thyroid hormones regulate several developmental, metabolic, and neural activities throughout the body. T3 affects almost every physiological process in the body, including growth and development, metabolism, body temperature, and heart rate. Production of T3 and its prohormone, thyroxine (T4), is activated by thyroid-stimulating hormone (TSH) and released from the pituitary gland. This pathway is part of a closed-loop feedback process when elevated concentrations of T3 and T4 in the blood inhibit the production of TSH in the pituitary gland. As concentrations of these hormones decrease, the pituitary gland increases the production of TSH. Through these processes, a feedback control system stabilizes the number of thyroid hormones in 100 1.0 in the bloodstream. The concentration of serum T4 is 20 times that of T3.

    Circulating levels of T4 are much more significant than T3 levels, but T3 is the more metabolically active hormone (3-4 times more potent than T4). However, its effect is briefer due to its shorter half-life. Elevated T3 and T4 are typical in patients with hyperthyroidism, but in a small subset of hyperthyroid patients, only T3 is elevated (T3 toxicosis). Triiodothyronine values greater than 2 ng/mL in adults or children are consistent with hyperthyroidism or high thyroid hormone-binding proteins. Diminished T3 and T4 are standard in patients with hypothyroidism, and T3 levels are frequently low in sick or hospitalized euthyroid patients.

  • Structure