Electrochemical Sensor for Ultrasensitive Determination of Doxorubicin and Methotrexate Based on Cyclodextrin‐Graphene Hybrid Nanosheets

In this work, an electrochemical sensor based on a cyclodextrin‐graphene hybrid nanosheets modified glassy carbon electrode (CD‐GNs/GCE) was proposed for the ultrasensitive determination of doxorubicin and methotrexate. The peak currents of doxorubicin and methotrexate on the CD‐GNs/GCE increased 26.5 and 23.7 fold, respectively, compared to the results obtained on the bare GCE. Under optimized conditions, the linear response ranges for doxorubicin and methotrexate are 10 nM–0.2 µM and 0.1 µM–1.0 µM, with detection limits of 0.1 nM and 20 nM, respectively. The sensor showed the advantages of simple preparation, low cost, high sensitivity, good stability and reproducibility. These properties make the prepared sensor a promising tool for the determination of trace amounts of doxorubicin and methotrexate in biological, clinical and pharmaceutical fields.