Implementation of an electronic tongue by flow detection of drinking water contaminants

Abstract

This work aims to prepare, characterize and develop a polymeric sensorial system to evaluate water quality by application of low cost interdigitated electrodes. The sensorial system, which must be applied to water quality monitoring, will be constituted by interdigitated graphite microelectrodes coated with nanostructured films of conductive polymers. The specificity of nanostructured sensors occurs as consequence of the application of films with nanometric thickness as sensitive layer, which allows direct interaction of polymeric nanocomposite layer and the chemical substance in analysis (analyte). The National Laboratory of Nanotechnology to Agrobusiness (Laboratório Nacional de Nanotecnologia para o Agronegócio / LNNA), is already in operation at Embrapa Instrumentation, in such a way one of the research themes aims the development, characterization and the application of nanostructured sensors to water quality determination. The sensors which must be applied to electronic tongue to water quality evaluation are composed by three elements: an substract, the interdigitated electrode and the sensitive layer. In this work, the sensitive layer will be composed by nanocomposites containing conductive polymers. In this way, this project proposes the design of interdigitated graphite electrodes by Line Patterning technique by a fast and low cost alternative method, aiming advances in electronic tongue to water quality evaluation. Moreover, novel methodologies to film deposition will be tested, providing a better reproductibility and validation of sensors response. Different polymers will be used to films nanostructuration, which will be characterized in terms of thickness, morphology and roughness, applying thechniques as scanning electron microscopy (SEM) and atomic force microscopy (AFM), as well as spectroscopic techniques (ultraviolet visible (UV-Vis) and Fourier transformed infrared (FTIR)) and X-ray diffatometry (XRD). By electronic tongue analysis, it is intended evaluate its viability as a device to evaluate the quality of potable water in relation to contaminants, as organophosphate pesticides. (AU)