Fabrication of Novel Modified Glassy Carbon Electrode for Determination of Toxic Phenol

Phenol and a considerable number of its derivatives are important toxic compounds and are extensively used in several industrial processes such as plastics, dyes, pesticides, papers, and petrochemical products. It is also produced in our body during food intake. As a result, phenols are often detected in water, soil and sediment samples. Phenol is used in the cleaning process of bacteria and fungi and for the treatment of sour threat as a paste and solution in medicine due to its disinfectant properties. Phenol today is not only threating the human health but also is a major source of pollutant, thus, it carries a potential risk for usage. Owing to their poor biodegradability, high toxicity and ecological aspects, phenol should be determined quantitatively when the sample is analyzed by sensitive analytical methods [1]. Phenol can be bind onto an electrode surface thus a polymerization process takes places on the modified electrode surface. The binding of phenol on the electrode surface enable us to determine phenol at very low concentrations. Voltammetric techniques require a small amount of sample volume thus help us to determine phenol and its derivatives [2]. Recently, metal nanoparticles have paid much attention due to their enhanced catalytic properties in various chemical reactions. Many reports established that the metal nanoparticles had high yields in catalyzing due to their smaller size (1- 100 nm), and they possess unique exhibit unique physical, chemical and electronic properties which are different from the bulk materials, and it can be used to construct novel and enhanced sensing devices, particularly, electrochemical and biosensors [3]. In this work, we tried to develop a specific sensor electrode for the determination of phenol by modifying GCE surface using CoFe2O4 nanoparticles and (14E)-4-((E)-4-(2-hydroxybenzylideneamino)phenoxy)-N-2- 421 hydroxybenzylidenebenzenamine (see fig. 1). After the modification process, the electron transfer becomes easier and faster. For the calibration curve, a series of standard phenol solution between 1.0×10-3 M and 1.0×10-8 M was prepared. By using this calibration method, the amount of phenol was determined as 8.33×10-5 M in natural decayed leaves. Detection limit was obtained as low as 1.0×10-8 M. By using this developed sensor electrode one can easily quantitatively determine phenol at very low concentrations. This study was successfully applied to the real samples for phenol determination. Fig. 1. Chemical structure of (14E)-4-((E)-4-(2-hydroxybenzylideneamino)phenoxy)-N-2- hydroxybenzylidenebenzenamine