Biolayer Interferometry

Short explanation of Biolayer Interferometry

Bio-Layer Interferometry (BLI) is a core technology used by Adaptyv for measuring protein binding interactions. BLI is a label-free, optical technique that monitors real-time changes in the interference pattern of light reflected from a sensor surface. These changes occur when molecules bind to or dissociate from the surface, providing precise kinetic and equilibrium data about the interaction.

How BLI Works:

1. Immobilization of the Protein or Target: One molecule (e.g., a protein or a target) is immobilized onto a biosensor. This molecule is referred to as the ligand.

2. Introduction of the Analyte: The other interacting molecule (e.g., a protein variant being tested) is flowed over the biosensor in solution. This molecule is referred to as the analyte.

3. Measurement of Binding Events: When the analyte binds to the ligand, there is an increase in the optical thickness at the sensor’s surface, causing a detectable shift in the interference pattern of light.

4. Kinetics and Equilibrium Data: By tracking how the interference pattern changes over time during both the binding (association) and unbinding (dissociation) phases, BLI provides:

   • Association Rate Constant (k_on): How quickly the analyte binds to the ligand.

   • Dissociation Rate Constant (k_off): How quickly the analyte dissociates from the ligand.

   • Equilibrium Dissociation Constant (K_D): The overall strength of the interaction, calculated as k_off/k_on..