Fiber-based Surface Plasmon Resonance Sensor for Lead Ion Detection in Aqueous Solution

Maghemite/reduced graphene oxide nanocomposite has been successfully deposited onto the surface of a gold-coated D-shaped optical fiber. The synergetic combination of gold, graphene, and iron oxide nanoparticles has shown enhancement of the resonance field and sensitivity of the fiber-based plasmonic sensor. In particular, the sensor exhibited its capability to detect lead ions (Pb 2+ ) in aqueous solution via monitoring the spectral response of the sensor probe to different concentrations of Pb 2+ . A sensor sensitivity of 1.2 nm per μg/L was attained at the lowest detected Pb 2+ concentration, which is 0.001 ppm (limit of detection). This robust, compact, and highly sensitive fiber-based plasmonic sensor will be of a great interest for an in situ and real-time water safety environmental monitoring.