Surface Plasmon Resonance
Surface plasmon resonance (SPR) is a phenomenon that allows real-time, label-free detection of biomolecular interactions.
SPR occurs when polarized light strikes an electrically conducting surface at the interface between two media. This generates electron charge density waves called plasmons, reducing the intensity of reflected light at a specific angle known as the resonance angle, in proportion to the mass on a sensor surface.
Applications of SPR include biotherapeutic and drug discovery research, as well as protein activity and stability analysis in biopharmaceutical production.
Follow label-free interactions in real-time
In Biacore instruments from GE Healthcare, target molecules, most frequently proteins, are immobilized on a prepared gold sensor surface and a sample containing a potential interacting partner in solution is injected over the surface through a series of flow cells.
During the course of the interaction, polarized light is directed toward the sensor surface and the angle of minimum intensity reflected light is detected. This angle changes as molecules bind and dissociate and the interaction profile is thus recorded in real time.
For most applications, a dextran matrix enables molecules to be immobilized on the sensor surface. As light does not penetrate the sample, interactions can be followed in colored, turbid, or opaque samples. No labels are required and detection is instantaneous.
Applications of SPR include drug biotherapeutic discovery research, and protein activity and stability analysis.
Biacore SPR systems provide quantitative interaction data on specificity, concentration, kinetics and affinity