Development of a gold nanoparticle-based lateral-flow strip for the detection of dinitolmide in chicken tissue.

Dinitolmide is a nitro amide coccidiostat used in poultry feed, and is a potential threat to the environment and human health. In this study, a monoclonal antibody (mAb) against dinitolmide was prepared and an immunochromatographic assay (ICA) was developed to detect residual dinitolmide in chicken tissue. The results show that the mAb exhibited high sensitivity, with a limit of detection as low as 9.01 ng mL-1. A cross reactivity test revealed that the mAb also had good specificity for dinitolmide. This ICA method showed a visible limit of detection of 2.5 μg kg-1, and a cut-off value of 25 μg kg-1 for testing dinitolmide in chicken sample extract by using the naked eye. Importantly, these observations using our ICA, were comparable to other methods of detection such as liquid chromatography, tandem mass spectrometry and indirect competitive enzyme-linked immunosorbent assays (IC-ELISA). These data suggest that our ICA method is a reliable, portable, and high-throughput method for the detection of dinitolmide residues in chicken tissue.