Electrochemical determination of artemisinin based on signal inhibition for the reduction of hemin.

A novel electrochemical sensor was constructed for the determination of artemisinin (ART) based on the inhibition of redox for hemin caused by ART. As far as we know, this strategy for ART determination may be proposed for the first time. In this work, untreated multi-walled carbon nanotubes were cast on the glassy carbon electrode (GCE) as conductive carrier. We prepared a bimetallic organic framework named FeGd-MOF and combined it with hemin by a simple physical mixed method. Then, we fabricated the working electrode by layer-by-layer modification and immobilization. The sensor measured by the differential pulse voltammetry (DPV) technique had calibration curves for the determination of ART, which was 0.3-350 μM with the correlation coefficient R2 = 0.9998. Furthermore, the obtained linear range could be practically used in real sample analysis such as dried leaves of Artemisia apiacea. Under the optimized condition, the electrochemical sensor exhibited high sensitivity, good stability, and excellent anti-interference performance. The limit of detection (LOD) for this sensor was 0.17 μM (signal to noise ratio, S/N = 3), which was much lower than that for some other reported electrochemical sensors. The recovery rates were in the range of 99.54-104.34% in real samples, indicating that the sensor had good repetition and high accuracy. Graphical abstract.