Page 54 - Book of Abstracts
P. 54

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
   49   50   51   52   53   54   55   56   57   58   59