Development of a polyclonal antibody-based indirect competitive enzyme-linked immunosorbent assay to detect dufulin residue in water, soil and agricultural samples

Abstract

ABSTRACTDufulin (DFL) is a potent, new-generation agrochemical that protects crops, such as tobacco, from viruses. Herein, for the first time, we developed a sensitive and specific polyclonal antibody-based indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) to detect DFL residues in samples. The assay showed high sensitivity and specificity to DFL, with a half maximal inhibitory concentration (IC50) of 48.5 ng ml−1 and limit of detection (IC20) of 2.5 ng ml−1. The average recovery of DFL in different spiked samples, such as tobacco, rice, tomato, cucumber, soil and water, was in the range of 70.7–138.8%. A statistically significant correlation was observed between our developed ELISA and previously established methodology of high-performance liquid chromatography with a diode array detector. These results indicate our assay is a potentially useful analytical tool for rapid detection of DFL residue in actual samples.