Multifunctional plasmonic optical nanosensor based on ring resonator supercells for early pregnancy diagnosis using...

This research presents the design and modeling of a novel multifunctional plasmonic optical nanosensor for the early diagnosis of pregnancy using urine samples. The sensor features a unique architecture based on a ring resonator supercell, which generates three distinct resonance modes in the near-infrared spectrum. A key innovation is that each resonance mode operates independently, effectively tripling the device's data acquisition capability from a single measurement. The operational principle relies on detecting minute changes in the refractive index of urine caused by varying concentrations of the human chorionic gonadotropin hormone. Through rigorous simulation using the Finite-Difference Time-Domain method, the sensor demonstrates high performance, achieving a maximum sensitivity of 891.36 nm/RIU and a superior figure of merit of 21.26 RIU⁻¹. The study concludes that this robust, multimode platform holds significant potential for highly sensitive, non-invasive, and early-stage biomedical diagnostics.