Metasurface-Enhanced Sensing Platforms for Chemical, Biological, and Environmental Monitoring: Recent Advances and Future Perspectives

The growing demand for sensitive, selective, and rapid detection of trace analytes in complex matrices is driving the development of compact optical sensing platforms. Metasurfaces can strengthen light–matter interactions through subwavelength field confinement and resonance engineering, thereby enhancing spectroscopic signals and sensitivity to analyte-induced refractive-index changes. This review examines the physical principles, material platforms, sensing mechanisms, and applications of metasurface-enhanced sensing in chemical analysis, biosensing, and environmental monitoring. Metallic, high-index dielectric, two-dimensional, and functional materials are discussed in relation to plasmonic and Mie resonances, Fano interference, and quasi-bound states in the continuum. Across these applications, optical enhancement alone does not guarantee strong analytical performance. Results depend on analyte access to the enhanced field, the selectivity of the sensing interface, and the extent of matrix interference. Further progress will require reproducible fabrication, stable operation, consistent evaluation protocols, validation with real samples, and readout systems suitable for portable use.