Synthesis and Characterization of Electrochemical Sensor Based on Polymeric /TiO₂ Nanocomposite Modified with Imidizolium Ionic Liquid for Determination of Diclofenac

摘要

A novel, simple and sensitive polymeric nanocomposite electrochemical sensor based on polymeric /TiO2 nanoparticles mixed with 1-butyl-3-methylimidazolium Chloride [BMIM]Cl ionic liquid andcoated with a polymeric layer of poly(3, 4-ethylene-dioxythiophene) (PEDOT) was fabricated fordiclofenac sodium (DCF) determination. The morphology and composition of the polymericnanocomposite was characterized by means of scanning electron microscopy equipped with energydispersive X-ray spectroscopy (SEM-EDX) and transmission electron microscopy (TEM). X-raydiffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were also used. The cyclicvoltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance (EIS) spectrawere recorded. All results sustained the electrochemical enhancement for the polymericnanocomposite sensor, which ascribed to the beneficial effect of both TiO2 nanoparticles andImidazolium ionic liquid with the conducting behavior of the polymeric layer. Where, the peakcurrents for (DCF) at PEDOT/TiO2/[BMIM]Cl/CPE show a great enhancement with a linear responsein the concentration range from 5.0?10?6?1.0?10?4mol L-1 . The limit of detection (LOD) was foundto be 1.17×10-8 mol L-1. Additionally, high selectivity of the polymeric nanocomposite sensor wasnoticed in presence of high concentration of ascorbic acid (AA) and uric acid (UA). Finally, themodified sensor was successfully applied for determination of (DCF) in its pure form, pharmaceuticalsamples of Voltic tablets and in urine samples with good agreement between the added and recovery.