Ionic silsesquioxane film immobilized on silica applied in the development of carbon paste electrode for determination of methyl parathion
- 344 Downloads
A mesoporous silica-based hybrid material composed of silica xerogel modified with an ionic silsesquioxane, which contains the 1,4-diazoniabicyclo[2.2.2]octane chloride group, was obtained. The silsesquioxane film is highly dispersed on the surface. This hybrid material was utilized to develop a carbon paste electrode (CPE) for determination of methyl parathion. Transmission FTIR, elemental analysis and N2 adsorption–desorption isotherms were used for characterization of the material. The electrochemical behavior of methyl parathion was evaluated by cyclic voltammetry and differential pulse voltammetry. It was observed a linear response to methyl parathion in the concentration range from 1.25 × 10−7 to 2.56 × 10−6 mol L−1 by employing the carbon paste electrode, in Britton–Robinson buffer solution (pH 6). The achieved detection limit (3 SD of the blank divided by the slope of calibration curve) was 0.013 µmol L−1 and sensitivity was 6.3 µA µmol L−1. This result shows the potentiality of this electrode for application as electrochemical sensor for methyl parathion.
KeywordsCharged organosilanes Sol–gel Water soluble polymers Charged silsesquioxane coating Organophosphorous pesticides Chemically modified electrodes
The authors are grateful to CNPQ (Conselho Nacional de Desenvolvimento Científico e Tecnológico), FAPERGS (Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul) and CAPES (Coordenação de Aperfeiçoamento Pessoal de Nível Superior) for their financial support and fellowships.
- 13.Jeyapragasam T, Saraswathi R, Chen S-M, Lou B-S (2013) Int J Electrochem Sci 8:12353–12366Google Scholar
- 27.Tamborim SM, Azambuja DS, Arenas LT, Costa TMH, Benvenutti EV (2008) Patente PI 0800519-2 (in Portuguese)Google Scholar
- 31.Gregg SJ, Sing KSW (1982) Adsorption, surface area and porosity, chapters 3 and 4. Academic, LondonGoogle Scholar