US Patent 7286235 - Surface plasmon resonance device with nanoporous dielectric

http://www.freepatentsonline.com/7286235.html

Surface plasmon resonance (SPR) is a technique used to detect biomolecules adsorbed on metal surfaces. Prisms used for SPR include a buffer layer having a refractive index that matches the sample under detection but the limitation of a matching refractive index reduces the materials that can be used for such buffer layers. This patent from Samsung teaches using nanoporous dielectric material with tunable refractive properties to expand operability. Claim 1 reads:

1. A surface plasmon resonance device comprising: a transparent substrate; a porous dielectric layer formed on a top surface of the transparent substrate; a thin metal layer formed on the porous dielectric layer; and a prism attached on a bottom surface of the transparent layer.