Detection and quantitative analysis of carbendazim herbicide on Ag nanoparticles via surface-enhanced Raman scattering

• Published in: Journal of Raman spectroscopy 2015-11, Vol.46 (11), p.1095-1101
• Main Authors: Furini, Leonardo Negri, Sanchez-Cortes, Santiago, López-Tocón, Isabel, Otero, Juan Carlos, Aroca, Ricardo F., Constantino, Carlos José Leopoldo
• Format: Article
• Language: English
• Subjects: Ag nanoparticle; carbendazim; Colloids; fungicide; Fungicides; Low concentrations; Mathematical analysis; Nanoparticles; Raman scattering; Silver; Surface chemistry; surface-enhanced Raman scattering
• ISSN: 0377-0486; 1097-4555
• DOI: 10.1002/jrs.4737

Carbendazim (MBC) is a fungicide widely used in agriculture, and there are serious concerns regarding the health risks that could be caused by this fungicide. Here, we explore its ultrasensitive detection by surface‐enhanced Raman scattering (SERS). First, to obtain maximum SERS signal, the adsorption of the target molecule onto metallic surface is essential. Therefore, we study the adsorption of the MBC onto the nanoparticle surface by SERS under different experimental conditions, such as different synthesis methods of nanoparticle, variable excitation wavelength, and fungicide concentration with the aim to detect MBC at low concentrations. Experiments are carried out with three kinds of colloidal nanoparticles: Ag and Au reduced by citrate and Ag reduced by hydroxylamine. However, mainly Ag colloids are highly efficient in the SERS detection of MBC. In addition, theoretical calculations of MBC Raman spectrum and that of the surface complex are used to help with the understanding the mechanisms responsible for the interaction between MBC and Ag. Ultraviolet–visible absorption spectroscopy showed displacement to the red of the plasmon resonance of Ag colloid in the presence of MBC. Copyright © 2015 John Wiley & Sons, Ltd. The use of surface‐enhanced Raman scattering (SERS) as analytical tool is a challenge because of SERS signal fluctuations. However, in a dynamic range, it is possible to obtain a stable and reproducible SERS signal. We report an analytical curve for the carbendazim pesticide using the SERS signal. This result enables an easy and fast method to detect carbendazim at low concentrations. Furthermore, we report a high affinity of carbendazim to silver nanoparticles, which can be an advantage in environmental control.