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Updated: May 19, 2026

Titration ELISA as a Method to Determine the Dissociation Constant of Receptor Ligand Interaction
Published on: February 15, 2018
Study of antibody/antigen binding kinetics by total internal reflection ellipsometry.
Ieva Baleviciute1, Zigmas Balevicius, Asta Makaraviciute
1Department of Physical Chemistry, Faculty of Chemistry, Vilnius University, Naugarduko 24, 03225 Vilnius, Lithuania. zbalevicius@ar.fi.lt
Total internal reflection ellipsometry (TIRE) reveals distinct kinetics for biosensing layer formation. Antibody structure (intact vs. fragmented) significantly impacts antigen interaction residence time, crucial for sensor development.
Area of Science:
- Biophysical Chemistry
- Surface Science
- Biosensor Technology
Background:
- Biosensing relies on specific antibody-antigen interactions.
- Understanding immobilization and interaction kinetics is crucial for biosensor performance.
- Total internal reflection ellipsometry (TIRE) offers sensitive surface analysis.
Purpose of the Study:
- To investigate the kinetics of biosensing layer formation using TIRE.
- To analyze antibody immobilization and subsequent antigen interaction kinetics.
- To compare the influence of intact versus fragmented antibodies on these processes.
Main Methods:
- Application of Total Internal Reflection Ellipsometry (TIRE) for real-time monitoring.
- Development of a novel method analyzing nonlinear changes in ellipsometric parameters Δ(t) and Ψ(t).
- Kinetic analysis incorporating partial reversibility of monolayer formation.
Main Results:
- Ellipsometric parameter Δ(t) is sensitive to initial interactions, while Ψ(t) is sensitive to steady-state conditions.
- Immobilization rates were similar for intact and fragmented antibodies.
- Residence time was 25x longer for intact antibody layers during formation, but antigen interaction was 8x longer with fragmented antibodies.
Conclusions:
- Antibody structure (intact vs. fragmented) significantly affects antigen interaction kinetics.
- TIRE provides sensitive insights into the dynamic processes of biosensing layer formation and interaction.
- The findings are valuable for optimizing antibody-antigen based biosensor design.
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