Synthesis of N-Doped Graphene Quantum Dots from Cellulose and Construction of a Fluorescent Probe for 6-Mercaptopurin Quantitative Detection

With cellulose as the precursor and ethylenediamine as the N source, N-doped graphene quantum dots (N-GQDs) were synthesized by a simple and feasible one-pot hydrothermal method. The whole process did noSchemet need a strong acid or strong base and avoided interference from inorganic salt residues. The whole process lasted only 3 h and avoided any complex postprocessing. Because of the outstanding optical properties of N-GQDs, a high-efficiency 6-mercaptopurine fluorescent probe based on the inner filter effect of fluorescence was established. The detection range was 0.2–60 μM and the detection limit was 0.05 μM. This method can preliminarily detect 6-mercaptopurine in human urine and avoids any sample preparation or extraction in advance and brings satisfactory results.