Portal de Periódicos da CAPES

Artigo Produção Nacional Revisado por pares

BIBTEX RIS

MWCNT/zirconia porous composite applied as electrochemical sensor for determination of methyl parathion

2020; Elsevier BV; Volume: 309; Linguagem: Inglês

10.1016/j.micromeso.2020.110583

1873-3093

Karine dos Santos Caetano, Danielle S. da Rosa, Tânia Mara Pizzolato, Pâmela Andréa Mantey dos Santos, Ruth Hinrichs, Edílson V. Benvenutti, Sı́lvio L.P. Dias, Leliz T. Arenas, Tânia Maria Haas Costa,

Analytical chemistry methods development

A selective, sensitive, quickly responsive and simple sensor for methyl parathion (MP) detection was developed using a composite based on a nearly 45% by weight of highly dispersed multiwalled carbon nanotubes (MWCNT) in a zirconia matrix, synthesized by sol-gel method. The composite MWCNT/zirconia showed a mesoporous nature, presenting a high surface area of 135 m2 g−1, where morphology and texture of MWCNT were preserved. The modified carbon paste electrode, obtained with this porous composite, presented an electroactive area of 7.4 mm2, showing a good response for MP detection. The electrochemical parameters for MP were obtained by differential pulse voltammetry (DPV) with detection limit of 9.0 × 10−9 mol L−1 and sensitivity of 1.475 μA μmol−1 L in a linear interval of 19.9 × 10−6 at 176.8 × 10−6 mol L−1. The electrode presented good selectivity in the presence of different interferences; it also showed good repeatability with RDS 0.91% for 13 cycles and reproducibility with RSD 14.2% in measurements. The sensing platform was tested in an ethanolic soybean extract with addition of methyl parathion at concentrations of 160; 180 and 200 × 10−6 mol L−1. The recoveries varied from 102 to 113%, and the relative standard deviation was 5.2%. The developed sensor demonstrated to be adequate for its utilization in the determination of methyl parathion with the purpose to ensure food safety.