Evidence of Core-Shell Formation between NdFeO3 Nano-Perovskite and Ionic Liquid Crystal and Its Application in Electrochemical Sensing of Metoclopramide

Abstract

A simple and sensitive electrochemical method for determination of metoclopramide was developed based on the in-situ modification of carbon paste electrode (CpE) with NdFeO3 (NF) nano-perovskite and 2-chloro-1,3-dimethyl-imidazolinium hexafluorophosphate ionic liquid crystal (ILC) in presence of sodium dodecyl sulfate (SDS); NFILCMCpE…SDS. A core-shell formation between NdFeO3 and ILC was confirmed affecting the catalytic activity of the nanocomposite. XRD, FTIR, TEM, BET, SEM and EDAX were used to elucidate the orthorhombic structure of NdFeO3 and give a complete characterization of the proposed composite sensor. Cyclic voltammetry and electrochemical impedance spectroscopy measurements revealed enhanced electrochemical activity for metoclopramide at the proposed sensor surface. The components of the composite sensor exhibit synergistic role in enhancing the sensor signal toward the drug. A linear calibration curve for metoclopramide was obtained at the proposed sensor in the concentration range of 0.4 μmol L−1 to 300 μmol L−1 with detection limit of 1.91 nmol L−1 and sensitivity of 203.56 μA/mmol L−1. NFILCMCpE…SDS was successfully applied for the sensitive determination of metoclopramide in its commercial tablets and real samples; urine and blood serum. Also, the proposed sensor exhibited anti-interference properties toward metoclopramide determination in presence of common interferents, pain relief drugs or neurotransmitters. The proposed sensor was very stable toward the electrochemical response of metoclopramide up to one month of storage.