Colóquio 02/06/2023: Strength, kinetics and specificity of biomolecular interactions revealed by label-free imaging biosensor

Optical surface biosensors measure very small changes in the refractive index at an interface due to the binding of biomolecules in solution onto immobilized molecular probes. A sensitive biosensor of this class can be realized by fine-tuning the interference between reflections from a thin dielectric layer on a glass substrate. We used this approach to study different molecular recognition processes involving DNA, RNA, and proteins aiming at dissecting the diverse phenomena involved in surface binding, such as transport limitations, electric potential, and cooperative binding. The main factors affecting the strength, kinetics, and specificity of biomolecular interactions on a surface are discussed with the aim of rationally designing novel diagnostic assays with enhanced performance.