Voltammetric determination of methylparaben and its DNA interaction using a novel platform based on carbon nanofibers and cobalt-nickel-palladium nanoparticles

A novel platform based on carbon nanofibers (CNFs) and nickel-cobalt-palladium nanoparticles was prepared for quantifying methylparaben (MPB) in pharmaceutical, cosmetic and urine samples. X-ray diffraction method (XRD) and Fourier transform infrared spectroscopy (FTIR) were utilized for characterizing the surface layer. The proposed electrode, (Co-Ni-Pd)NPs-CNFs/GCE, was applied to the electrode reaction of MPB. Compared with several other electrodes, the proposed voltammetric platform, (Co-Ni-Pd)NPs-CNFs/GCE, exhibited great electrocatalytic activity for MPB with an improved voltammetric peak at 0.768 V. A linear concentration range of 3-300 nM was obtained at (Co-Ni-Pd)NPs-CNFs/GCE with a detection limit of 1.2 nM for MPB. The proposed electrode exhibited good reproducibility (RSD of 1.06%), high precision (RSD of 1.27%) and excellent accuracy (98.05-103.4%) for MPB. The proposed sensing platform, (Co-Ni-Pd)NPs-CNFs/GCE, was successfully applied for quantifying MPB in several pharmaceutical, cosmetic and urine samples. Such a sensitive quantification of MPB makes this procedure of great interest for analyzing samples for the public health care. In addition, it was shown that MPB could bind to DNA via intercalation with a binding constant of 1.56 (+/- 0.25) x 10(4). (C) 2016 Elsevier B.V. All rights reserved.