Electrochemical Determination of Anti-Cancer Drug Pazopanib with High Selectivity and Sensitivity Using Molecularly Imprinted Polymer-Modified Glassy Carbon Electrode

Abstract

Pazopanib (PZB) is a multiple kinase inhibitor used for the treatment of advanced renal cell carcinoma and soft tissue sarcoma. This work focuses on achieving high selectivity and sensitivity for the determination of PZB using a molecularly imprinted polymer (MIP)-based electrochemical sensor. The MIP-based sensor was fabricated by thermal polymerization (TP) directly on a glassy carbon electrode (GCE). The electrochemical response of the 4-ABA/PZB@MIP/GCE sensor was investigated using differential pulse voltammetry (DPV). The characterization of the sensor in terms of morphology and electrochemistry was performed using scanning electron microscopy (SEM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The 4-ABA/PZB@MIP/GCE sensor exhibited a linear response ranging from 1.0 × 10–13 M to 1.0 × 10–12 M with a limit of detection (LOD) and limit of quantification (LOQ) of 1.04 × 10–14 M and 3.48 × 10–14 M, respectively. The applicability of the sensor was evaluated by determining commercial samples of human serum and tablets, and good recoveries were obtained. The results showed that the sensor could identify PZB, compared to structurally analogous drugs such as axitinib, nilotinib, and erlotinib. The interfering substances commonly found in biological fluids were investigated. Finally, the sensor design was validated using a non-imprinted polymer-based GCE.