A molecularly imprinted electrochemical sensor based on highly selective and an ultra-trace assay of anti-cancer drug axitinib in its dosage form and biological samples.

In this study, a novel, fast, selective, and sensitive molecularly imprinted polymer (MIP)-based electrochemical sensor was developed to determine axitinib (AXI) at low concentrations in pharmaceutical dosage forms and human serum. The newly developed MIP-based sensor (MIP@o-PD/GCE) was designed through electropolymerization of functional monomer o-phenylenediamine (o-PD) in the presence of a template molecule AXI, on a glassy carbon electrode (GCE) using cyclic voltammetry. Differential pulse voltammetry and electrochemical impedance spectroscopy (EIS) techniques were employed for removal and rebinding processes, optimization of conditions, as well as for performance evaluation of MIP@o-PD/GCE using [Fe(CN)6]3-/4- as the redox probe. Under the optimum experimental conditions, MIP@o-PD/GCE shows a linear response toward AXI in a range of 1 × 10-13 M - 1 × 10-12 M. The limit of the detection value of MIP@o-PD/GCE was found as 0.027 pM while the limit of the quantification was obtained as 0.089 pM, respectively. To demonstrate the applicability and validity of the developed sensor, it was successfully applied to tablet dosage form and human serum sample. The selectivity of the sensor was qualified by comparing the binding of AXI, erlotinib, dasatinib, nilotinib, and imatinib, which are similarly structured and in the same group of anticancer drugs. MIP@o-PD/GCE sensor showed a significant selectivity toward AXI. The non-imprinted polymer (NIP) based GCE was prepared and used to control the analytical performance of the MIP-based electrochemical sensor.