Electro-optically modulated biomolecular-interaction analysis sensor

This paper focuses on developing the platform technology of real-time biomolecular-interaction analysis (BIA) sensor chips. A detection scheme using the electro-optically modulated surface plasmon resonance (SPR) is suggested to advance the sensor features in reducing measurement complexity and time. The SPR method of a BIA sensing system detects slight changes of refractive index due to the biomolecular interaction at the solid-liquid interface. The most sensitive interrogation method among the possible conventional schemes is to measure the SPR angle of the attenuated total reflection. The electro-optical modulation replaces the mechanism of angle measurement not only to increase the speed but also to reduce the size. Recent progress of the multilayer SPR provides an effective mean of tailoring the microchip. Several multilayer configurations have been studied in this paper to realize the electro-optical SPR sensing. Especially, the long-range mode of surface plasmon was investigated to achieve the high-resolution and high-sensitivity detection.