Construction a magneto carbon paste electrode using synthesized molecularly imprinted magnetic nanospheres for selective and sensitive determination of mefenamic acid in some real samples

A novel magneto multiwalled carbon nanotube/carbon paste electrode (MMW/CPE) for the determination of mefenamic acid (MFA) was introduced. Magnetic molecularly imprinted polymer nanoparticles (MMIPNPs) were synthesized and then added to the solution of MFA. After stirring for 20 min, the MMW/CPE was immersed in the solution of MFA (contain MMIPNPs) and the MMIPNPs were captured by it. Then oxidation of MFA was analyzed by differential pulse voltammetry (DPV). Electrochemical impedance spectroscopy, cyclic voltammetry, and DPV were employed to characterize the MMW/CPE. The MMIPNPs exhibited a high selectivity and sensitivity toward MFA. The effect of various experimental parameters including pH, MMIPNPs dosage, stirring time, accumulation potential and time on the voltammetric response of MFA were investigated. Under the optimal conditions, selective detection of MFA in a linear concentration range of 2.0-1000.0 nmol L−1 was performed with the detection limit of 1.2 nmol L−1 (3S/N). To further study the practical applicability of this method, it was applied to the analysis of some real samples and the obtained results were satisfactory.