Ionic silsesquioxane film immobilized on silica applied in the development of carbon paste electrode for determination of methyl parathion

• Published in: Journal of sol-gel science and technology 2014-11, Vol.72 (2), p.282-289
• Main Authors: Caldas, Elisangela Muncinelli, de Menezes, Eliana Weber, Pizzolato, Tânia Mara, Dias, Silvio Luis Pereira, Costa, Tania Maria Haas, Arenas, Leliz Ticona, Benvenutti, Edilson Valmir
• Format: Article
• Language: English
• Subjects: Buffer solutions; Carbon; Ceramics; Chemical sensors; Chemistry; Chemistry and Materials Science; Chlorides; Colloidal gels. Colloidal sols; Colloidal state and disperse state; Composites; Electrochemical analysis; Electrodes; Exact sciences and technology; General and physical chemistry; Glass; Inorganic Chemistry; Materials Science; Methyl parathion; Nanotechnology; Natural Materials; Optical and Electronic Materials; Original Paper; Pastes; Restrictions; Silicon dioxide; Slopes; Voltammetry
• ISSN: 0928-0707; 1573-4846
• DOI: 10.1007/s10971-014-3367-8

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 N 2 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.