In-Lattice Occupied\nRare Earth Metal Chalcogenide\nNanocomposites as Electrocatalysts for Selective Detection of Promethazine\nHydrochloride

This study aims to provide a widely applicable electrochemical\nsensor for the determination of the first-generation antihistamine,\npromethazine hydrochloride (PMH), which accounts for its efficacy\nin treating allergic reactions, motion sickness, and sedating human\npatients before surgery or medical treatment. Along with its use in\nclinical settings, it can also induce some undesirable side effects.\nFor safety measures, it is necessary to detect this drug in biological\nfluids and environmental samples. For this purpose, a one-pot hydrothermal\nmethod is used to construct a 0-D CdTe anchored on rod-shaped CeO<sub>2</sub> electrocatalyst-modified GCE for the electrochemical detection\nof PMH. Various spectroscopic techniques were used to characterize\nour proposed CdTe-CeO<sub>2</sub> nanocomposite. Further, the electrochemical\nproperties of the CdTe-CeO<sub>2</sub>/GCE sensor were investigated\nby using EIS and CV techniques. Under an optimized condition, our\nproposed sensor effectively detects PMH using CV and DPV techniques\nin a pH-7 medium. As a result, our electrocatalyst provides a higher\nsensitivity (2.295 μA μM<sup>–1</sup> cm<sup>–2</sup>) with a low limit of detection of 0.0037 μM and a wide linear\nrange of 0.001–113.719 μM. Moreover, our proposed sensor\nexhibits high selectivity and outstanding reproducibility, which indicates\nthat CdTe-CeO<sub>2</sub>/GCE configuration could be a feasible alternative\nfor assessing PMH.