Highly Sensitive Glucose Concentration Detection Using a Fabry–Perot Fiber-Optic Sensor Integrated With a Microfluidic Chip

This study presents a glucose concentration detection system based on a microfluidic chip integrated with a Fabry–Perot interferometer optical fiber sensor (FPIOFS). The Fabry–Perot resonator is positioned on the bottom plate of the detection area, where a silver (Ag) thin film with high reflectivity in the infrared range is sputtered, in conjunction with a single-mode fiber end face, to generate the Fabry–Perot resonance effect, thereby enhancing measurement sensitivity. The microfluidic chip was fabricated using a laser cutting machine and thermal pressing method, allowing easy and rapid production. The system exhibits high signal stability, repeatability, and linearity in glucose concentration measurements. The detection range spans from 2 to 1000 mg/dL, with a sensitivity of $4.655\times 10^{\mathbf {-{3}}}$ nm/(mg/dL) and a high linearity of 0.905. The combination of optical fiber sensing and microfluidics presents a promising approach for noninvasive and efficient biomedical analysis, offering new possibilities for point-of-care diagnostics and personalized medicine.