Biomarker detection and bulk refractive index sensing are important across multiple industries for early medical diagnosis and fluid quality control. Technological innovations have been developed to speed up diagnoses however, their bulky size, high price tag, and complex device infrastructure limit their use to highly skilled environments like hospitals, large food processing plants, and research labs. In this article, we develop a compact and relatively inexpensive refractive index sensing device based on resonant dielectric photonic metasurfaces. These dielectric resonances support dipole and higher order Mie resonances enabling the design of refractive index sensors with varying sensitivities to their ambient environment. Our device assembly allows for the fabrication of multiple metasurfaces using these varying resonant types resulting in device multiplexing on the same chip. Aqueous solutions of sodium chloride and calcium chloride as well as a synthetic coronavirus biomarker is detected on our device. This device has prospects of enabling facile, fast, and highly sensitive measurements with adequate limits of detection for personalized biomedical diagnosis.
