Materials Sciences and Applications, 2017, 8, 798-810 http://www.scirp.org/journal/msa ISSN Online: 2153-1188 ISSN Print: 2153-117X DOI: 10.4236/msa.2017.811058 Oct. 24, 2017 798 Materials Sciences and Applications Electrochemical Sensors Based on Modification of Carbon Fiber Microelectrode by Nickel Phthalocyanine Polymer for 3-Methyl-4-Nitrophenol Analysis in Water Yibor Fabrice Roland Bako 1 , Boukare Kabore 2 , Issa Tapsoba 1 1 Laboratoire de Chimie Analytique, Environnementale et Bio-organique (LCAEBiO), Département de Chimie, Université Ouaga 1 Pr Joseph Ki-Zerbo, Ouagadougou, Burkina Faso 2 Bureau des Mines et de la Géologie du Burkina (BUMIGEB), Ouagadougou, Burkina Faso Abstract 3-methyl-4-nitrophenol (MNP) is the main by-product of the organophos- phate insecticide fenitrothion (FT), used in locust control. MNP is highly tox- ic because it is an endocrine disruptor and then may cause adverse in the bio- logical systems. Then, it is necessary to develop analytical methods for deter- mination of this pollutant in the environment. In this sense, we reported herein the development of an electrochemical sensor for the detection of 3-methyl-4-nitrophenol (MNP), one of the metabolites of fenitrothion (FT), by using naked and modified carbon fiber microelectrode (CFME) by nickel tetrasulfonated phthalocyanine polymer (CFME/p-NiTSPc). The voltammo- gram showed that MNP presents one irreversible anodic peak corresponding to the oxidation of the phenol group at 0.9 V vs Ag/AgCl. The effect of pH of the buffer on the peak current and SWV parameters such as frequency, scan increment and pulse amplitude were investigated in order to optimize the electrochemical response of the sensor. The obtained results lead to the fol- lowing optimum value: pH = 6; frequency = 25 Hz, pulse amplitude = 50 mV, scan increment = 10 mV. With these optimum values, the calibration curves show that the peak current varied linearly upon MNP concentration leading to a limit of detection (LoD) for naked CFME close to 3 µg/L whereas for CFME modified by p-NiTSPc, it reaches 0.75 µg/L. This results prove that the presence of p-NiTSPc increasing the sensitivity of the sensor could be used to monitor 3-methyl-4-nitro- phenol residue in real matrix. Keywords 3-Methyl-4-Nitrophenol, Carbon Fiber Microelectrode, How to cite this paper: Bako, Y.F.R., Ka- bore, B. and Tapsoba I. (2017) Electrochemi- cal Sensors Based on Modification of Carbon Fiber Microelectrode by Nickel Phthalocya- nine Polymer for 3-Methyl-4-Nitrophenol Analysis in Water. Materials Sciences and Applications, 8, 798-810. https://doi.org/10.4236/msa.2017.811058 Received: August 24, 2017 Accepted: October 21, 2017 Published: October 24, 2017 Copyright © 2017 by authors and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access