Fabrication of an electrochemical molecularly imprinted polymer sensor for determination of ketorolac trometamin using multivariate optimization using multi-walled carbon nanotubes

Ketorolac trometamin (KT) is used for the short-term treatment of moderate to severe pain in adults. It is usually used before or after medical procedures or after surgery. One of the most promising separation techniques that have emerged during the last decade is based on the use of molecularly imprinted polymers (MIPs). Recently, MIPs have attracted a broad interest from researchers engaged in sensor development (2013, 2014). The general principal of molecular imprinting is based on such a process where functional monomers are copolymerized in the presence of a target analyte (the imprint molecule) which acts as a molecular template (2012). A novel electrochemical sensor using molecularly imprinted polymer (MIP) technique for the detection of KT was developed. The sensitive MIP sensor for KT was electrochemically synthesized onto multi-walled carbon nanotubes (MWCNTs) immobilized pencil graphite electrode (MWCNTs/PGE) surface. The multivariate methods were used to optimize the voltammetric response of modified electrode for determination of KT (2014). A Plackett–Burman design (PBD) was chosen as a screening method to estimate the relative influence of the factors that could have an influence on the analytical response (current). The significant variables including MWCNTs (A), deposition time (B), pyrrol concentration (C), KT concentration (D), number of cycles ( E ), pH (F), scan rate (G), loading time ( H) and stirring rate ( I) were optimized using central composite design (CCD). The optimum values of significant parameters i.e. A, C, D, F and I were obtained 0.36g.L-1, 421s, 0.07mol.L-1, .002 mol.L-1, 10, 4, 103mV.s-1, 14min and 400r.p.m, respectively. The equation for sensor response based on the optimized parameters was obtained as : MIP = -200.7 + 0.1081B + 2.619G + 9.74 H Under the optimal conditions, the sensor showed a high selectivity and excellent stability toward KT and used to detect the analyte in real samples successfully. This work discusses an 107 electrochemical sensor, which combines the advantages of the use of MIPs with those of employing electrode surface modification and multivariate optimization techniques.