Synergistic performance of FeWO₄-WO₃composite for enhanced electrocatalytic detection of azathioprine in biological and environmental samples

Long-term use of the immunosuppressant drug azathioprine (ATN) and its residues is highly hazardous for human health and the environmental system. Herein, we prepared an electrocatalyst of iron tungstate-tungsten trioxide (FeWO4-WO3) composite by the hydrothermal method, and various physicochemical studies were conducted to confirm the formation of the catalyst. The proposed catalyst of FeWO4-WO3 composite on the glassy carbon electrode (FeWO4-WO3/GCE) showed a nanomolar detection limit with a higher sensitivity of 22 nM and 1.093 μA μM-1 cm-2 by the help of differential pulse voltammetry (DPV) method. Subsequently, FeWO4-WO3/GCE showed good repeatable, reproducible, and anti-interference phenomena towards ATN detection. Furthermore, the designed electrode achieved good storage stability of 99.07 % after three weeks. To attain a virtuous recovery result in bio and environmental samples of human urine, river water, lake water, and sewage water samples. This prominent activity of the FeWO4-WO3/GCE towards the ATN in real sample analysis makes it a promising electrochemical sensor for the ATN detection.