Surface plasmon sensor for lead ion (Pb2+) detection using graphene oxide – Gold coated tilted fiber Bragg grating

Abstract

In this study, the use of a surface plasmon sensor based on a gold-coated tilted fiber Bragg grating (Au-TFBG) functionalized with graphene oxide (GO) for the detection of lead ions (Pb2+) was demonstrated. To facilitate the modification of the Au-TFBG’s gold surface, cysteamine (Cys) was employed to form a self-assembled monolayer (Cys-SAM). This step was essential for binding the GO sheets on the Au-TFBG surface via the amine functional groups of Cys. Subsequently, the GO-COOH sheets were adsorbed onto the Au-linker surfaces. The sensor’s performance was assessed using several divalent metal ions, including Pb2+, Co2+, Cd2+, Ni2+, Zn2+, and Cu2+. Notably, the sensor exhibited the highest sensitivity for Pb2+. The measured sensitivity and limit of detection (LOD) were recorded at 0.018 dB/µM and 0.711 µM, respectively. Overall, the results demonstrate the potential of the GO-Au-TFBG sensor for sensitive and selective detection of Pb2+ ions, a capability that holds significant importance in environmental monitoring and industrial applications.

Keywords

• Surface plasmon resonance
• Graphene oxide
• Lead ions
• Tilted fiber grating