Novel paper- and fiber optic-based fluorescent sensor for glucose detection using aniline-functionalized graphene quantum dots

Abstract

Aniline functionalized graphene quantum dots (a-GQDs) is synthesized by microwave-assisted pyrolysis of fructose. After a-GQDs are modulated using phenyl boric acid (PBA), resulting in fluorescence quenching, the a-GQDs/PBA system are employed as a fluorescent turn-on sensor for the glucose detection by the specific reaction of PBA with glucose. The prepared fluorescent sensor using a-GQDs/PBA exhibits high sensitivity and selectivity toward glucose. In addition, the paper-based fluorescent sensor is prepared for portable sensing devices by printing the a-GQDs ink with a commercial inkjet printer, demonstrating a superior visual glucose detection and a good sensitive performance for the detection of glucose in a blood serum and tear samples. Furthermore, the a-GQDs/hydrogel film is evaluated for a wearable sensor as well as fiber optic-based sensor for highly sensitive and fast on-site glucose detection. The prepared fiber optic sensor exhibits remarkable glucose sensing performance with a fast response, a low detection limit of 2.1 μM and excellent recyclability. Finally, the a-GQD/PBA system exhibits excellent biocompatibility and was applied to detect glucose in HeLa cells with satisfactory results. These results provide a novel approach for developing low-cost and flexible sensors for the portable and visual detection of glucose with high sensitivity and selectivity.