Nickel‐Based Metal‐Organic Framework/Crosslinked Tubular Poly(3,4‐ethylenedioxythiophene) Composite as an Electrocatalyst for the Detection of Gallic Acid and Tinidazole

Abstract Nickel‐based metal‐organic framework (Ni‐MOF) embedded in tubular poly(3,4‐ethylenedioxythiophene) (T‐PEDOT) composites was first synthesized through the in situ growth of Ni‐MOF with T‐PEDOT. The incorporation of T‐PEDOT and Ni‐MOF enhances the conductivity of Ni‐MOF/T‐PEDOT, reduces aggregation and restricts the size of Ni‐MOF, and exposes more active sites of the Ni‐MOF. Compared with Ni‐MOF, Ni‐MOF/T‐PEDOT manifests improved electrocatalytic activity toward the oxidation and reduction of gallic acid and tinidazole, respectively. The Ni‐MOF/T‐PEDOT‐2/glassy carbon electrode (GCE) as a novel electrochemical sensor was constructed to detect two antibacterial drugs. Ni‐MOF/T‐PEDOT‐2/GCE shows two linear responses to gallic acid in the range of 0.8–25.5 μM and 25.5–150 μM, with a high sensitivity of 0.559 μA μM −1 . At the same time, Ni‐MOF/T‐PEDOT‐2/GCE exhibits two linear responses to tinidazole in the range of 0.7–35 μM and 35–255 μM. Therefore, Ni‐MOF/T‐PEDOT‐2/GCE could be used to detect gallic acid and tinidazole in real samples with satisfactory results. Recovery values varied from 95.1 to 104.2 % for gallic acid sensing and 94.2 to 104.2 % for tinidazole sensing, which demonstrates that the sensor has practical application for gallic acid and tinidazole detection. Our work offers an efficient strategy for fabricating a new electrocatalysts based on MOFs and tubular conductive polymer.