Graphene-Based Surface Plasmon Resonance Sensor for Milk Adulteration Sensing

Adulteration of milk and dairy products is the most basic and common malpractice all over the world. In this study, a bimetallic surface plasmon resonance sensor is proposed which also includes the utilization of extensive properties of the two-dimensional material, i.e., graphene to enhance the sensor performance further. The refractive index of the adulterated milk samples was calculated analytically to measure the shift in the resonance angle of reflection. It is observed that the bimetallic sensor provides much better performance than a single layer sensor in terms of sensitivity as well as detection accuracy. It is also observed that addition of a graphene layer can be used to enhance the sensitivity performance of the models. Through this study, the highest sensitivity of 137.032 °/RIU is achieved from the proposed sensor structure. As per best of authors knowledge this is first time when chip based SPR sensor is proposed for real time milk adulteration detection.