Glucose biosensing based on a hydrogel optical fiber immobilized with glucose oxidase

In this study, a glucose biosensor based on a hydrogel optical fiber immobilized with a fluorescence indicator and glucose oxidase (GO) is presented. The Hydrogel optical fiber was fabricated by mixing 2-hydroxy-2-methyl-propiophenone as a photo initiator, polyethylene glycol diacrylate (PEGDA) as a base, and deionized water with a certain ratio, irradiated under UV light. The oxygen-sensitive fluorescent indicator, o-phenanthroline ruthenium, and GO were introduced into the core of the hydrogel optical fiber. The sensitivity and efficiency of the system were optimized by varying the concentration of GO and the fluorescent indicator, and the sensing characteristics at different pH and temperatures were investigated. The experimental results showed that the performance of the sensor head was best at 25 °C and a pH within the range of 4.5–6. The relationship between the glucose concentration and fluorescence ratio I/I0 within the range of 20–100 μg/mL is linear with a correlation coefficient of R2 = 0.9934. Moreover, the repeatability of the sensing system is good. Due to its good molecular permeability and biocompatibility, a hydrogel optical fiber glucose sensing system can be widely used in biomedical fields.