Detection of carbofuran in fruits and vegetables by Raman spectroscopy combined with immunochromatography

Abstract

It has long been desired to develop rapid methods for the rapid identification and quantification of pesticides and their metabolites. Carbofuran, a representative pesticide of the carbamate group, is highly systemic and is used on vegetables, fruits and grains, which has led many countries to test for residues in food and the environment. In this study, gold and silver composite core–shell (Au@Ag) nanoparticles were used to label the carbofuran antibody and Raman molecule 5,5-dithiobis-2-nitrobenzoic acid (DTNB) to synthesize Raman immune probes. The signal value of DTNB was read using a Raman spectrometer, and the quantitative detection technology of carbofuran was established based on lateral flow immunochromatographic assay (ICA) combined with surface-enhanced Raman spectroscopy (SERS). SERS-ICA is a rapid, quantitative and ultrasensitive test for the determination of carbofuran in fruits and vegetables with a sensitivity of 0.1 pg mL⁻¹. Consequently, the results demonstrate that the SERS-based lateral flow immunosensor developed in this study has the advantages of excellent assay sensitivity and remarkable multiplexing capability, and thus it will have great application potential in food safety monitoring.