Razzino Claudia A, Sgobbi Lívia F, Canevari Thiago C, Cancino Juliana, Machado Sergio A S
Instituto de Química de São Carlos, Universidade de São Paulo, PO Box 780, 13560-970 São Carlos, SP, Brazil.
Instituto de Química de São Carlos, Universidade de São Paulo, PO Box 780, 13560-970 São Carlos, SP, Brazil.
Food Chem. 2015 Mar 1;170:360-5. doi: 10.1016/j.foodchem.2014.08.085. Epub 2014 Aug 27.
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.
本文描述了一种用介孔二氧化硅/多壁碳纳米管薄膜修饰的玻碳电极在伏安法测定杀菌剂多菌灵（CBZ）中的应用。通过以HF作为催化剂的溶胶-凝胶法获得了杂化材料（SiO₂/MWCNT）。在pH 8.0时，采用方波伏安法在相对于Ag/AgCl为+0.73 V的电位下测量对CBZ的安培响应。SiO₂/MWCNT/GCE对CBZ的响应线性范围为0.2至4.0 μmol L⁻¹。使用统计方法计算得出的检测限为0.056 μmol L⁻¹。SiO₂/MWCNT/GCE传感器的主要特点是灵敏度高、检测限低且稳定性好，可用于未经处理的实际样品中CBZ的测定。此外，该方法对CBZ相对于橙汁中的主要成分抗坏血酸和柠檬酸具有显著的选择性。优异的灵敏度和选择性使得该方法在橙汁样品中检测CBZ具有可行性。
