Rapid detection of the neonicotinoid insecticide imidacloprid using a quenchbody assay

Abstract

Contamination of the land and water by neonicotinoid insecticide residues is currently a severe environmental problem. However, the traditional methods for pesticide residue analysis are time consuming and laborious. To tackle this problem, here we describe a novel quenchbody (Q-body) immunoassay reagent that allows the rapid and sensitive detection of imidacloprid, one of the most frequently used neonicotinoid pesticides, in aqueous solution. A Q-body comprises an antibody Fab fragment that is site-specifically labeled with a fluorescent dye. The Fab fragment quenches the dye with its internal tryptophan residues via photoinduced electron transfer. The subsequent addition of imidacloprid stabilizes the antibody structure and displaces the quenched dye to the outside of the protein, resulting in increased fluorescence. The constructed Q-body assay exhibited a high dynamic range and a low limit of detection (10 ng mL), and the entire assay procedure could be completed in a few minutes. The assay showed a low cross-reactivity with possible interfering analogous compounds, indicating that it has a good selectivity. Hence, the developed Q-body assay has excellent potential as a universal technology for monitoring neonicotinoid residues in environmental and food samples. Graphical abstract A novel quenchbody (Q-body) immunoassay reagent that allows the rapid and sensitive detection of imidacloprid, one of the most frequently used neonicotinoid pesticides, in aqueous solution was developed. The addition of imidacloprid stabilizes the Q-body structure and displaces the quenched dye to the outside of the protein, resulting in increased fluorescence. The constructed Q-body assay exhibited a high dynamic range and a low limit of detection (10 ng mL), and completed in a few minutes.

Detection and destruction of HER2‐positive cancer cells by Ultra Quenchbody‐siRNA complex

“…We have found that Q‐body made of antibody Fab fragment (Ultra Q‐body [UQ‐body]) is more stable, and generally gives a higher antigen‐dependent signal than the corresponding single‐chain Fv‐based Q‐body. UQ‐bodies have been successfully constructed for the detection of various substances, including small molecules, such as illegal drugs (Abe et al, 2014), pesticides (Zhao, Dong, Jeong, Okumura, & Ueda, 2018), and peptides, as well as large proteins, such as influenza virus hemagglutinin (Jeong, Dong, & Ueda, 2018) and the tight junction‐associated membrane protein, claudin (Jeong et al, 2017). We have successfully imaged claudin‐positive cancer cells by fluorescence microscopy without any washing steps, which could potentially be harnessed for use in cancer diagnostics.…”

Simultaneous determination of acetamiprid and 6‐chloronicotinic acid in environmental samples by using ion chromatography hyphenated to online photoinduced fluorescence detector

“…Their particular characteristics of low toxicity for warm-blooded animals, the wide spectrum of efficiency, selective activity against various insects, and versatility for various agricultural practices have increased the world insecticides market share by up to 25% in 2014 [2][3][4]. This growing use of the neonicotinoids is causing various serious impacts on the ecosystem such as extinct of butterflies, the disappearance of birds, crumple of honey bee colonies, and mammals toxicity are few of them [5][6][7]. Besides, these are also causing direct or indirect adverse effects on consumers health, and risk for wild/honey bees is real [8,9].…”

Synthesis of core‐shell magnetic molecularly imprinted polymer for the selective determination of imidacloprid in apple samples

“…Imidacloprid is one of the best‐selling neonicotinoid insecticides and is applied to a wide variety of crops, including fruits and vegetables . Due to its high persistence and water solubility, imidacloprid can be easily absorbed by plant roots and transported throughout the whole body .…”