A novel electrochemical method has been developed, based on a covalent organic framework (COF) and reduced graphene oxide (rGO), to detect fentanyl and alfentanil. COF nanomaterials with chrysanthemum morphology obtained by solvothermal reaction contain rich active sites for electrochemical catalytic reaction, thus improving the detection performance of the designed sensor. Reduced graphene oxide improves the sensor's sensitivity due to enhanced electron transfer. Under optimized experimental conditions, the fabricated electrode presents a linear range of 0.02 to 7.26 μM for alfentanil and 0.1 to 6.54 μM for fentanyl, with detection limits of 6.7 nM and 33 nM, respectively. In addition, the sensor possesses excellent selectivity, outstanding reproducibility, and acceptable stability. The proposed sensor is feasible for the reliable monitoring of fentanyl and alfentanil in human serum samples, with acceptable reliability and high potential in real-world applications. Finally, the electrochemical characteristic fingerprint of fentanyl is investigated by studying the electrochemical behavior of alfentanil and fentanyl on the electrode surface.
Keywords: Alfentanil; Covalent organic framework; Electrochemical detection; Fentanyl; Modified electrode; Oxidation mechanism; Square-wave voltammetry.
© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.