Single-atom Iron-doped Graphene Quantum Dots Synthesized by a Green Chemical Method for High-efficiency Glucose Detection

Abstract

Nanozymes have emerged as a promising class of nanomaterials that mimic the catalytic activity of natural enzymes. In this study, we present the synthesis and characterization of single Fe atom-doped graphene quantum dots (FeN/GQDs) as nanozymes for glucose detection. The FeN/GQDs are prepared through a facile hydrothermal method using pineapple leaves as a precursor, allowing for large-scale production. The synthesis process involves anchoring single Fe atoms to the graphene quantum dots through Fe-N coordinate bonds, which serve as catalytic sites. The catalytic activity of FeN/GQDs is evaluated by investigating their peroxidase-like (POD-like) activity using three chromogenic systems: TMB, OPD, and ABTS. The FeN/GQDs exhibit excellent catalytic efficiency, comparable to natural enzymes and other single atom nanozymes. The underlying catalytic mechanism is explored using the EPR-trapping technique. To demonstrate the practical application of FeN/GQDs, they are utilized as colorimetric nanomaterials for glucose detection. By combining glucose oxidase with FeN/GQDs, a colorimetric response is obtained and compared with other materials. The FeN/GQDs demonstrate high sensitivity and selectivity, making them suitable for glucose biosensing. The hydrothermal synthesis method employed in this study simplifies the production of FeN/GQDs, offering scalability and cost-effectiveness for large-scale applications. Overall, this study introduces a novel synthesis method for FeN/GQDs as single atom nanozymes for glucose detection. The exceptional catalytic activity and stability of FeN/GQDs highlight their potential for various biomedical applications. The findings contribute to the development of nanozyme-based glucose detection technologies, enabling rapid and accurate glucose monitoring in clinical diagnostics and other related fields.