Electrochemical Sensor Based on Perovskite Hydroxide and Carbon Black Nanocomposite for the Selective Detection of Crizotinib

Crizotinib (CZT) is an anaplastic lymphoma kinase (ALK) inhibitor used for the treatment of lung cancer. The selective detection of CZT in human biological samples is crucial for therapeutic studies. Electrochemical sensors have become essential in pharmaceutical analysis due to their high selectivity, fast response, low costs, simplicity, and portability. Here, an effective and novel electrochemical sensor based on a perovskite hydroxide CoSn(OH)₆/carbon black (CB) nanocomposite was designed for the highly selective detection of CZT on a glassy carbon electrode (GCE) surface. Characterization techniques such as field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and electrochemical methods such as electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and differential pulse voltammetry (DPV) confirmed the structural and electrochemical properties of the nanocomposite. The sensor exhibited a wide linear range of 0.001 to 2400 nM, a limit of detection (LOD) of 0.0003 nM, and acceptable selectivity, reproducibility, repeatability, and stability for CZT detection. Finally, the designed electrode was used to determine CZT in a real sample, displaying its promise for pharmaceutical and biomedical applications.