Surface Plasmon Resonance Refractometer Based on Smartphone Platforms

Abstract

In this research, we demonstrate the surface plasmon resonance (SPR) refractometer based on smartphone platforms. The principle design of this SPR refractometer was configured to use a fan-shaped beam from smartphone screen as a light source and front phone camera as a detector. The optical element used in this system is a single integrated device, fabricated by the epoxy resin. The performance of the smartphone-based SPR refractometer was evaluated by detecting the sucrose/water solutions with different concentrations ranging from 0 % to 20 % by weight. The results show that the shift of resonance angle increases linearly with the sucrose concentration. The sensitivity and Brix value resolution of this SPR refractometer are 2.094 Int/Brix and 0.06 Brix, respectively. Moreover, this SPR refractometer could be used to determine the Brix value of commercial soft drink, fruit juices, energy drink and sports drink with the maximum error less than 3 % from standard refractometer.