Optical Fiber Based FPI-Tapered Refractive Index and Temperature Biosensor

The work presented explores the integration of intrinsic Fabry-Perot Interferometric (FPI) microcavities along tapered optical fiber sensors to produce a multiparameter biosensor for targeting the detection of lower concentrations of glucose and temperature variations. The study focuses on incorporating microcavities as localized resonators to optimize response to temperature and refractive index (RI) changes. Through experiments, we demonstrate that the introduction of microcavities within tapered single-mode optical fibers is a sophisticated technique that underpins the development of advanced biosensors with the potential for multiparameter-based biosensing, given the capability of signal demultiplexing, further fostering the lab-on-fiber concept. The biosensor demonstrated promising results in detecting temperature changes in the range of 20 to $40^{\circ} \mathrm{C}$, leading to a sensitivity of $8.9 \mathrm{~ p m} /^{\circ} \mathrm{C}$ and glucose concentrations in the detection range of 0.8 to $3 \mathrm{mg} / \mathrm{mL}$ (expected human glucose levels) with a sensitivity of $5.78 \times 10^{-4}$ Count.mL/mg.