TiO2 Nanoparticles Decorated Graphene Nanoribbons for Voltammetric Determination of an Anti-HIV Drug Nevirapine

Daniel Apath,Munyaradzi Shumba,Mambo Moyo

doi:10.1155/2020/3932715

Abstract

In the present study, electrochemical behavior of nevirapine on a glassy carbon electrode (GCE) modified with TiO2 nanoparticles decorated graphene nanoribbons was investigated. Characterization of different components used for modifications was achieved using Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The electrochemical behavior of nevirapine on the modified electrodes was examined using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), chronoamperometry (CA), and differential pulse voltammetry (DPV). A considerable oxidation potential decrease of +352 mV for nevirapine in 0.1 M phosphate-buffered saline (PBS), pH 11.0, was achieved due to synergy offered by graphene nanoribbons and TiO2 compared to graphene nanoribbons (+252 mV) and TiO2 (−37 mV), all with respect to the glassy carbon electrode. Under optimized conditions, DPV gave linear calibrations over the range of 0.020–0.14 µM. The detection limit was calculated as 0.043 µM. The developed sensor was used for determination of nevirapine in a pharmaceutical formulation successfully.

Highlights

We have fabricated a simple, cheap glassy carbon electrode (GCE) modified with TiO2/graphene nanoribbons (GNRs) as an electrochemical sensor for nevirapine
Several analytical methods, such as reversed phase high-performance liquid chromatography (RPHPLC) [4] and capillary electrophoresis [2], have been used for quantifying NVP in pharmaceutical combinations and some real samples. e growing demand for NVP biomolecule stimulates a search for new and even more effective monitoring techniques, which give better insight on their reported analytical work. erefore, it is appropriate to develop new and/or improve on the existing analytical techniques regarding their qualitative and quantitative determination in various matrices, namely, human serum, urine, breast milk, and pharmaceutical formulations. e development of sensors with high sensitivity to promote safety and efficiency during administration to patients who depend on these different biomolecules for life support is important
Fourier transform infrared spectroscopy (FT-IR) spectra of TiO2, GNR, and TiO2/GNR composite are shown in Figure 1(a). e characteristic peaks in (b) were assigned as follows: 1654 cm−1 attributed to the stretching vibrations of carboxyl (-COOH) and at 1130 cm−1 corresponding to C-O-H bending and C-OH. e presence of such peaks can be used to explain the hybrid structure of graphene nanoribbons

Summary

Introduction

We have fabricated a simple, cheap glassy carbon electrode (GCE) modified with TiO2/GNRs as an electrochemical sensor for nevirapine. E electrochemical oxidation behavior of nevirapine was investigated by CV in 0.1 M PBS (pH 11.0) at modified electrodes (Figure 4(b)). E electrocatalytic oxidation of nevirapine with TiO2/GNR composite modified GCE showed improved behaviors.

Results

Conclusion