A Comparative Study of Molecular Imprinting Techniques Used for Fabrication of Electrochemical Sensor of Olaparib

Abstract

This study reported the molecular imprinting process investigated by two techniques: photopolymerization (PP) and thermal polymerization (TP). These techniques were integrated with an electrochemical sensor to determine the new generation anticancer drug Olaparib (OLP), which is a poly(ADP-ribose) polymerase (PARP) inhibitor with high sensitivity and selectivity. The PP-MIP film was formed by PP, while TP-MIP film was formed by TP on a glassy carbon electrode (GCE). In the PP-MIP(OLP)/GCE sensor, which was developed using PP, 4-aminobenzoic acid (4-AB) as a functional monomer was designed, and obtained in the presence of basic monomer (HEMA, 2-hydroxyethyl methacrylate), crosslinker (EGDMA, ethylene glycol dimethacrylate), and initiator (2-hydroxy-2-methyl propiophenone) by keeping it under a UV lamp at 365 nm. For TP-MIP(OLP)/GCE was obtained by using a mixture of 4-AB as a functional monomer, NH3 solution, surfactant sodium dodecyl sulfate (SDS), and tetraethyl orthosilicate (TEOS): ethanol (1:1, v/v) and keeping it in an oven at 50 °C for 40 min. After each process, the GCE surfaces were characterized via scanning electron microscope and electrochemical techniques (cyclic voltammetry and electrochemical impedance spectroscopy). The required optimization studies were performed for both techniques. After obtaining the optimum MIP-integrated electrochemical sensors, the analytical performances of PP-MIP(OLP)/GCE and TP-MIP(OLP)/GCE were evaluated, and the validation parameters were compared. The linear ranges of PP-MIP(OLP)/GCE and TP-MIP(OLP)/GCE are 0.1–1 nM. The PP-MIP(OLP)/GCE and TP-MIP(OLP)/GCE were applied to commercial serum samples and pharmaceutical dosage forms. The selectivity of proposed sensors was also proven using similar structures of OLP through imprinting factor. The results show that the proposed PP-MIP(OLP)/GCE and TP-MIP(OLP)/GCE sensors have good selectivity, high sensitivity, accuracy, and precision. The determination of OLP was achieved with these electrochemical sensors for the first time.