*4.2.1. Surface plasmon resonance (SPR)*

This technology is based on the generation of plasmons on a surface, which are oscillations of free electrons propagated parallel to the metal/medium interface, which allows to measure the changes in the refractive index of the sensor surface. The intensity variation of the reflected light and/or the angle of incidence tell us if there are molecular associations or dissociations, allowing to determine the relationship between the association and dissociation of biomolecules with each other. In addition, the SPR technology also allows evaluate the affinity and specificity of these interactions, facilitating the measurement of biomolecular interactions in real time with high sensitivity.
