Portable surface plasmon resonance (SPR) measurement device for sensing applications

This paper presents prototype design and fabrication of a portable surface plasmon resonance (SPR) measurement device based on angular interrogated Kretschmann configuration. Easy mount for the sensor chip with custom made syringe based fluid infusion system capable of pumping in microlitres makes them suitable for biosensing applications. The experimental device is driven by a single stepper-motor ensuring synchronous movement of light source and the detector which is critical requirement for effective prism based SPR measuring system. The developed system has a wide angular scanning range of 30°-80°for incident light with angular scanning accuracy of 0.005°, measuring 300mm x 250mm x 250mm and weighing ~3.5kg. Robust and miniaturized design with a simple stand-alone operation allows it to be operated by semi-skilled person in laboratories with limited facility. The device was calibrated using standard solutions of ethanol and sucrose for the real-time experimental measurement of SPR achieving maximum sensitivity of 229.43 degree/RIU.