Quantitative and rapid detection of spinosad and spinetoram by a gold nanoparticle-based immunostrip

Abstract

Spinosad (SPI) and spinetoram (Et-SPI) are currently among the most popular new insecticides because of their high efficiency and low toxicity. However, excessive residues in food still pose a potential risk to public health. Therefore, it is necessary to strengthen residue monitoring of the two insecticides based on a simple and rapid method. In this study, a highly sensitive mAb (6G9) against SPI and Et-SPI was prepared using the hapten SPI-HS and used to develop a colloidal gold nanoparticle-based immunochromatographic strip for the detection of SPI and Et-SPI in samples. The quantitative ranges of the developed strip for SPI and Et-SPI were 8.93–1633 ng g⁻¹ and 20.3–3555 ng g⁻¹ in rice, 32.6–785 ng g⁻¹ and 79.3–1862 ng g⁻¹ in tea, and 9.66–360 ng g⁻¹ and 23.9–931 ng g⁻¹ in onions, respectively. In addition, recovery rates ranged from 85.7% to 112.7% with a coefficient of variation <9.5%. Therefore, our developed method was sensitive and valid as a quantitative tool for the rapid monitoring of SPI and Et-SPI in foods.