Electrochemical Sensor for Selective Determination of Ketorolac Tromethamine based on Molecularly Imprinting Polypyrrole Modified with Functionalized Multi-wall Carbon Nanotubes in Pharmaceutical and Biological Samples

In this project, using a molecularly imprinting polypyrrole (MIP) modified with functionalized multi-wall carbon nanotubes (MWCNTs), a selective and sensitive electrochemical sensor constructed to measure ketorolac tromethamine (KT). Cyclic Voltammetry (CV), differential pulse Voltammetry (DPV) and chronoamperometry methods, respectively was performed in preparation of MIP, quantitative measurements and deposition of MWCNTs on the bare paper graphite electrode (PGE) surface. The nine factors were chosen for the investigation, which are: the concentration of MWCNTs, deposition time of MWCNTs onto the bare PGE surface, concentration of pyrrole, concentration of KT, number of cycles in electropolymerization, the pH of the polymerization solution, scan rate of CV process, electrode loading time, and stirring rate of loading solution. The multivariate methods, including Plackett-Burman design (PBD), and central composition design (CCD) were used for screening and optimizing of factors that could influence on the analytical response, respectively. Under the optimized conditions, the proposed MIP sensor showed a linear range from 4.0×10-6 to 6.0×10-3 M KT concentration with a correlation coefficient (R2) of 0.9903. The limit of detection was obtained 0.12 µM (3Sb/m, n=6) with a highly reproducible response (RSD 4.45%, n=4). The electrochemical sensor showed good results for the determination of KT in pharmaceutical and biological samples.