Surface Plasmon Resonance (SPR)

Surface Plasmon Resonance (SPR) is a technique used to detect molecular interactions in real-time without labels. It measures changes in the flow of light reflected from a thin metal film—usually gold—when molecules bind to its surface. As molecules attach or detach, they alter the local refractive index, which shifts the angle at which light resonance occurs. By monitoring this shift, SPR provides precise information about how molecules interact, including binding strength and rate, making it valuable in biological research, drug development, and diagnostics.