Interferometric surface plasmon resonance based on low-cost grating substrates

Abstract

Surface plasmon resonance (SPR) has been used for some time in chemical and biological sensors. Some of the schemes for exciting surface plasmons include prisms and gratings. Grating-based optical SPR sensors have been demonstrated, which use light intensity variations at resonance or wavelength interrogation. Recently, a gold grating made from a commercial recordable compact disk was used for excitation of surface plasmons and SPR imaging. In this paper, we present a new grating configuration that combines the benefits of multi-angle interrogation with interferometric measurement techniques. This gives array sensing capability over a wide refractive index range. The set-up is based on the gold grating of commercially available recordable compact disks, which are mass produced by injection-moulding, resulting in low cost and disposable grating substrates. The potential of using this system for large sample number analysis is demonstrated.