Fiber-Optic Surface Plasmon Resonance: Innovations in Optical Fiber Design and Plasmonic Interface Design Strategies

Surface plasmon resonance (SPR) biosensors have garnered significant attention due to their exceptional sensitivity and ability to conduct real-time, label-free detection, making them especially valuable for environmental sensing and diagnostics. However, conventional SPR systems frequently lack field applicability, portability, and integration, especially those that rely on large prism couplings. Fiber-optic SPR (FO-SPR) biosensors, which combine the flexibility, compactness, and remote sensing possibilities of optical fibers with the robust sensing capabilities of SPR, have become an appealing solution to these restrictions. The fundamental ideas and the most recent developments in FO-SPR technology are combined in this review. Even with their obvious benefits, FO-SPR systems still have to deal with issues including device repeatability, long-term signal stability, and fabrication complexity. To accelerate the advancement of next-generation FO-SPR biosensors that are highly sensitive, selective, compact, user-friendly, and ready for use in practical settings, this review aims to provide a comprehensive and easily navigable guide for researchers and engineers in the field.