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 (pb2+) in aqueous solution via monitoring the spectral response of the sensor probe to different concentrations of pb2+. a sensor sensitivity of 1.2 nm per μg/l was attained at the lowest detected pb2+ 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.