Fe-Co-Fe prussian blue analogues loaded nitrogen doped carbon quantum dots for effective epinephrine detection.

Epinephrine (Ep) is an important neurotransmitter, which plays an important role in the nervous system and glycogen metabolism of living organisms. Hence, a novel NCQDs/FeCoFe-PBA composite with FeCoFe-Prussian blue analogues (PBA) as the core and nitrogen-doped carbon quantum dots (NCQDs) as the shell was constructed by a one-pot hydrothermal method, and it was used for the efficient detection of Ep. As a good electroactive material, NCQDs in the composite not only improved the weak conductivity of FeCoFe-PBA, but also limited the self-aggregation of FeCoFe-PBA, and formed a uniform shell on FeCoFe-PBA. The heterogeneous structure formed between the core and shell layer resulting in NCQDs/FeCoFe-PBA nanocomposites with more active sites, electron transport channels and a larger effective surface area. Further, under optimal conditions, the electrochemical method was used to evaluate the NCQDs/FeCoFe-PBA sensor, and the results revealed that the sensor had exceptional sensing performance for Ep, with an excellent linear range from 0.01 to 306.7 μM and a low detection limit of 0.002 μM. Simultaneously, the practicality, repeatability, and stability tests yielded positive results, confirming the feasibility of practical development and application of NCQDs/FeCoFe-PBA.