Biomolecular interactions govern the everyday functions of the body and are typically measured using ligand-binding assays. An interaction system can be protein-ligand, protein-protein, protein-nucleic acid, but can also be more complex systems such as virus-like particles and antibody-drug conjugates.

Current label-free techniques are able to generate high-quality steady-state affinity and kinetics data that goes beyond yes-or-no answers from co-immunoprecipitation or the less-accurate ELISA studies.

In the era of rapidly evolving biologics, ligand-binding assays have gained importance in every step of drug discovery, drug development, pharmacokinetic analysis, safety, and immunogenicity evaluation, and biomarkers discovery processes. High-quality ligand-binding assay data on affinity and kinetics are an requirement for New Drug applications (NDAs).

Biomolecular parameters:

• Binding affinity – KD
• Binding kinetics – Kon and Koff (Ka and Kd)
• Binding thermodynamics (ΔH, ΔS, ΔG)
• Binding stoichiometry (n)