Biolayer interferometry (BLI) is one of the newer tool for characterization of binding ligand to protein and is an excellent complementary method to standard technique such as SPR and ITC. This technique uses fiber-optic biosensors for label-free real-time monitoring. It is performed in standard multi-well plates containing diluted solution of one binding partner in which a biosensor tip functionalized with the second partner is immersed (Figure 1). Upon irradiation of the functionalized biosensor with a white light, the detection of interferometry variation occurring during association/dissociation steps allows for the determination of kinetic and thermodynamic parameters of the interaction.
Figure 1 – principle of biolayer interferometry