In Situ Electrochemical Development of Highly Charged TiO 2 -NPs Nanoparticles Decorated With Reduced Graphene Oxide For The Detection of Trace Chloroquine In Contaminated Human Urine And Serum Samples

Abstract

An important step in the development of electrochemical sensors is the modification of the working electrode surface. In this study, a simple synthesis of TiO2 nanoparticles on reduced graphene oxide sheets was used as the basis for the development of an electrochemical sensor for the voltammetric measurement of chloroquine. This method allowed the fabrication of completely new, so-called modified electrodes with very high electrocatalytic activity and distinct chemical reactivity. Using a variety of techniques, the nanocomposites were characterized morphologically. XRD, IR, SEM, HRTEM, and BET revealed modifications of the functional groups and the attachment of titania to the reduced graphene oxide portion on the electrode surface, which can be used to explain the enhanced electrochemical performance of the TiO2-NPs @RGO /GCE. High electrocatalytic activity towards chloroquine molecules. The proposed TiO2 -NPs @RGO/GCE sensor demonstrated a wide linear dynamic range for chloroquine analysis from 10− 4 M to 10− 7 M with a detection limit LOD = 1x10− 8 M. The applicability of this device for the analysis of water, pharmaceutical, human urine and serum samples was demonstrated. For the samples examined, a recovery between 97% and 102% was achieved with acceptable recovery.