Page 54 - Book of Abstracts 2020

th
8 Biannual Conference on Chemistry - CHEM 08

Electrochemical Detection and Stability Indicating Study for

Sofosbuvir Based on Computationally Designed
Molecularly Imprinted/ Functionalized Multi-Walled

Carbon Nanotubes/ Reduced Graphene Oxide Sensor
Muhammed Abdel Hamid Abdel Tawab, Muhammad Gamal Abd El-
Moghny, Rasha Mohamed El Nashar
Chemistry Department, Faculty of Science, Cairo University, Giza, Egypt

ABSTRACT
A successful development for a rapid, sensitive and selective biomimetic
electrochemical sensor for sofosbuvir determination in the presence of its
degradation product and for stability indicating study was achieved. First,
computational calculations based on density functional theory (DFT) at the
B3LYP/6-31G(d) level were employed to screen different functional monomers
for the rational design of molecularly imprinted polymer (MIP). Based on the
computational calculations, the imprinted sensor active sites were engineered
via electropolymerization of ortho aminophenol (OAP) on a glassy carbon
electrode modified with functionalized multi-walled carbon nanotubes (f-
MWCNTs) and reduced graphene oxide (RGO) nanocomposite for sensitive
determination of sofosbuvir (SOFO). The stepwise fabrication steps of the sensor
were characterized by cyclic voltammetry (CV), electrochemical impedance
spectroscopy (EIS) and atomic force microscopy (AFM). Differential pulse
voltammetry (DPV) was employed for obtaining the calibration curve and
optimization of significant factors that control the sensor performance. Under the
optimum experimental conditions, the proposed sensor exhibited a linear range
from 0.53 ng/ml to 74.13 ng/ml and significant detection limit at 0.05 ng/ml (S/N
= 3) in addition to good reproducibility and selectivity. Finally, the imprinted
sensor was successfully applied for the analysis of SOFO in pure samples, two
different pharmaceutical formulations and electrochemical stability indicating
study.

Keywords: Molecular imprinting; Anti‒HCV; Electropolymerization; Sofosbuvir;
Density functional theory

BOOK OF ABSTRACTS CHEM 08 (2020) Page 53