Voltammetric determination of rivastigmine in pharmaceutical and biological samples using molecularly imprinted polymer modified carbon paste electrode

Abstract

Despite the increasing number of applications of molecularly imprinted polymers (MIPs) in analytical chemistry, the construction of a biomimetic voltammetric sensor remains still challenging. A new voltammetric sensor for rivastigmine (RIV) measurement is introduced. A RIV-selective molecularly imprinted polymer and a non-imprinted polymer (NIP) were synthesized in a non-covalent approach using methacrylic acid (MAA) as functional monomer and ethylene glycol dimethacrylate (EGDMA) as crosslinking monomer via a free radical polymerization and then were used for carbon paste electrode (CPE) preparation. The electrochemical behavior of the sensor toward RIV was investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The MIP embedded in the CPE, functioned as a selective recognition element and a pre-concentrator agent for RIV determination. The MIP-CPE showed very high recognition ability in comparison to NIP-CPE. The complete removal of RIV from polymer was confirmed by FTIR and TGA. Some parameters affecting sensor response were optimized, and a calibration curve was then plotted. A linear range of 2.0–1000μmolL−1 was obtained. The detection limit of the sensor was calculated to be equal to 0.44μmolL−1. This sensor was used successfully for RIV determination in capsule and spiked serum and urine samples.