title: Sensitive determination of carbendazim in orange juice by electrode modified with hybrid material.
abstract: This paper describes the application of a glassy carbon electrode modified with a thin film of mesoporous silica/multiwalled carbon nanotubes for voltammetric determination of the fungicide carbendazim (CBZ). The hybrid material, (SiO2/MWCNT), was obtained by a sol-gel process using HF as the catalyst. The amperometric response to CBZ was measured at +0.73 V vs. Ag/AgCl by square wave voltammetry at pH 8.0. SiO2/MWCNT/GCE responded to CBZ in the linear range from 0.2 to 4.0 μmol L(-1). The calculated detection limit was 0.056 μmol L(-1), obtained using statistical methods. The SiO2/MWCNT/GCE sensor presented as the main characteristics high sensitivity, low detection limit and robustness, allowing CBZ determination in untreated real samples. In addition, this strategy afforded remarkable selectivity for CBZ against ascorbic and citric acid which are the main compounds of the orange juice. The excellent sensitivity and selectivity yielded feasible application for CBZ detection in orange juice sample.
authors.affiliation: Instituto de Química de São Carlos, Universidade de São Paulo, PO Box 780, 13560-970 São Carlos, SP, Brazil.
authors.forename: Claudia A
authors.initials: CA
authors.lastname: Razzino
authors.affiliation: Instituto de Química de São Carlos, Universidade de São Paulo, PO Box 780, 13560-970 São Carlos, SP, Brazil.
authors.forename: Lívia F
authors.initials: LF
authors.lastname: Sgobbi
authors.affiliation: Instituto de Química de São Carlos, Universidade de São Paulo, PO Box 780, 13560-970 São Carlos, SP, Brazil. Electronic address: tccanevari@gmail.com.
authors.forename: Thiago C
authors.initials: TC
authors.lastname: Canevari
authors.affiliation: Instituto de Física de São Carlos, Universidade de São Paulo, PO Box 780, 13560-970 São Carlos, SP, Brazil.
authors.forename: Juliana
authors.initials: J
authors.lastname: Cancino
authors.affiliation: Instituto de Química de São Carlos, Universidade de São Paulo, PO Box 780, 13560-970 São Carlos, SP, Brazil.
authors.forename: Sergio A S
authors.initials: SA
authors.lastname: Machado
mesh_terms: D001562:Benzimidazoles / Q000008:administration & dosage* / Q000627:therapeutic use*; D001628:Beverages; D002219:Carbamates / Q000008:administration & dosage* / Q000627:therapeutic use*; D032084:Citrus sinensis; D004566:Electrodes; D006801:Humans; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010084:Oxidation-Reduction; D012822:Silicon Dioxide
chemical_list: D001562:Benzimidazoles; D002219:Carbamates; D037742:Nanotubes, Carbon; D012822:Silicon Dioxide; C006698:carbendazim
keywords: Carbendazim; Carbon nanotubes; Electrochemical sensor; Mesoporous silica; Pesticides