الفهرس 
Chapter 1: Introduction & Literature reviewOnly 14 pages are availabe for public view
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Abstract
Organic electrochemistry is a branch of science involved with studying the oxidation and reduction of organic compounds at electrode surfaces. It covers a number of applications such as electrosynthesis of organic compounds, CO2 electrolyzers, and fuel cells, as well as electroanalysis and electrodegradation of organic pollutants. In this thesis, the electroanalysis of some selected pesticides and organic dyes as organic pollutants in surface water has been carried out using novel sensors. In general, the system of the electrochemical-based sensor is composed of four main components: transducer, capture probe, reporter probe, and the signal transduction method. Herein, glassy carbon (GC) electrode as transducer, silver nanoparticles (AgNPs) capped by organic molecules as capture and reporter probes, and voltammetric methods as transduction methods have been selected for the detection of organic pollutants. First, AgNPs were synthesized via a direct chemical reduction using dissolved organic matter (DOM), natural latex (NL), mucilage, and gum Arabic as reducing and capping agents. The synthesized AgNPs were identified and characterized using ultraviolet visible spectroscopy, spectrofluorophotometer, particle size/zeta potential analyzer, and transmission electron microscope. Next, AgNPs were immobilized on GC electrode surface through sticking and transfer sticking techniques. Potentiostat device was used for the electrochemical measurements. Atrazine pesticide was detected using DOM-AgNPs/GC electrode on the basis of DOM-AgNPs aggregation and atrazine oxidation, while Eriochrome black T (EBT) dye was detected using NL-AgNPs/GC electrode on the basis of NL-AgNP displacement and EBT oxidation. Chlorpyrifos pesticide was also detected using DOM-AgNPs/GC, NL-AgNPs/GC, and Mucilage-AgNPs/GC electrodes on the basis of AgNP oxidation inhibition. Additionally, Methylene blue (MB) dye was determined using Gum Arabic-AgNPs/GC electrode on the basis of the Gum Arabic-AgNP and MB oxidation amplification. The validity of the four tested sensors was studied through the determination of the sensitivity, selectivity, limits of detection, limits of quantifications, and relative standard deviations. Moreover, the suitability of each sensor to be used in the detection of pollutants in real water (Nile River) samples was
evaluated.