A novel biochip detection system based on lateral SPR wave propagation theory

In this paper, we investigated the lateral SPR (surface plasmon resonance) propagation theory and implemented a novel optical SPR detection system, using a two-prism coupling method to excite the SPR and detect the lateral propagating SEW, which by enlarging the SPR sensing area thus enhances the detection sensitivity. From theoretical calculations, the propagation length increases with excitation wavelength and provides a detection sensitivity of /spl sim/1.05/spl times/10/sup -5/ RIU at /spl lambda/=790 nm. By measuring the propagation length (at fixed wavelength), or the resonant wavelength (at fixed lateral length), changes around the SPR, we can use this lateral SPR phenomenon for biochip applications.