Desenvolvimento de sensor eletroquímico utilizando eletrodo de Au modificado com Quantum Dot para determinação de ácido úrico

Abstract

The purpose of modifying the surface of an electrode is to increase its physico-chemical stability and interaction with a specific analyte, consequently entailing a better analytical response. Therefore, host-host systems are a good alternative for the development of systems with such purposes. The applications of quantum dots in systems with bases in the electrochemistry has increased considerably, due to its optical and electronic properties. In the present study, the goal was to develop an electrochemical sensor using β-cyclodextrin (β-CD) modified gold electrode and the quantum dot core shell, cadmium selenide / cadmium sulfide (CdSe/CdS). This system was characterized against electrochemical properties using cyclic voltammetry, differential pulse voltammetry, to such a sensor was given a new application, resulting in the study of electroanalytical profile for uric acid, this experiment was performed with great success, because the fruit of this work was published in annals of academic event. It was possible to obtain electrochemical detection by the cyclic voltammetry technique in the concentration range of 7 μmolL-1 to 300 μmolL-1 of uric acid. The interaction constant was calculated by the Languimur isotherm derivative, obtaining a value of 4.14 X 103 Lmol-1. Using differential pulse voltammetry, detection was obtained in the concentration range of 10 μmolL-1 to 300 μmolL-1. For the limit of detection, the value of 0.0415 μmolL-1 was obtained, and for the limit of quantification the value of 0.1333 μmolL-1 was obtained. That is, the study was finalized by doing everything that was proposed in the beginning.