Principles of biosensing with an extended coupling matrix and surface plasmon resonance

Surface plasmon resonance is one of the surface-oriented biosensing techniques that can be used to monitor biomolecular interactions. It is utilized in instrumentation for real-time biospecific interaction analysis capable of determining not only the concentrations of biomolecules but also kinetic constants, binding specificity, etc. In this contribution biosensing with surface plasmon resonance is reviewed. Special attention is given to an extended interaction matrix on the sensing surface, which enables the covalent binding of, e.g., antigens or antibodies. The surface plasmon resonance angle shifts are calculated as a function of the amount of organic material in the matrix. The influence of physical parameters, such as matrix thickness and wavelength of the light, on the expected performance is considered. Finally, a few illustrative experimental results obtained with a recently introduced commercial instrument are given.