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Updated: May 16, 2026

Bio-layer Interferometry for Measuring Kinetics of Protein-protein Interactions and Allosteric Ligand Effects
13:57

Bio-layer Interferometry for Measuring Kinetics of Protein-protein Interactions and Allosteric Ligand Effects

Published on: February 18, 2014

[Interaction of triiodothyronine-biotin conjugate with binding proteins in immunoassay systems]

M J Navakouskiĭ, I I Vashkevich, O V Sviridov

    Bioorganicheskaia Khimiia
    |November 30, 2012
    PubMed

    A new construction of a test-system for free thyroid hormone 3,3',5-triiodothyronine determination (free T3) in human blood serum in ELISA and IRMA variants was described. For this purpose a low-molecular weight bifunctional conjugate containing T3 and vitamin H (biotin, Bt) residues was synthesized. The conjugate (T3-Bt) can be bound via its biotin function to biotin-binding proteins on a solid phase whereas its T3-portion can interact with monoclonal antibody against T3 (anti-T3-MAb) labeled with horseradish peroxidase or iodine-125 in an enzyme immunoassay or an immunoradiometric assay system (ELISA or IRMA), respectively. The immunochemical interaction is hindered if the T3 residue takes part as a component of a preformed solid phase complex between T3-Bt and avidin. Computer modeling shows that in this complex glycan component of avidin shields iodothyronine residue. The binding of T3-Bt both with T3-free sites on anti-T3-MAb and the solid phase avidin achieves with help of a delayed T3-Bt addition into avidin-covered containers with preliminary co-incubated labeled anti-T3-MAb and an assayed T3 sample.

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