Detection of Triclabendazole and three metabolites in Bovine muscle samples with a Gold Nanoparticle-based Lateral Flow Immunoassay
In this study, a highly sensitive monoclonal antibody (mAb) against Triclabendazole (TCD) and its metabolites was produced by using a novel hapten. The subclass of this mAb was IgG2a, its IC50 values were 1.49-3.58 ng mL-1 against TCD and its metabolites, and its affinity constant was 5.46×109 mol L-1. We then went on to develop using, gold nanoparticles as label, a mAb-based lateral flow immunoassay (LFIA) for the rapid screening of TCD and its metabolites in foodstuff. The LFIA-based test strip was assembled using routine procedures. All of the following parameters were optimized including: the pH, minimum antibody concentration needed for the synthesis of the AuNP-mAb conjugate, the best coating antigen and its concentration, the volume of the mAb-AuNP conjugate and optimal diluent buffer constituents. Under optimized conditions, the cut off values for the LFIA were 10μg kg-1 for TCD, TCD-SO and TCD-SO2, and 25μg kg-1 for Keto-TCD, and the limits of detection (LODs) were 0.11μg kg-1 for TCD, 0.28μg kg-1 for TCD-SO, 0.38μg kg-1 for TCD-SO2, and 0.47μg kg-1 for Keto-TCD. The ranges of quantitative detection were 0.22-5.41μg kg-1 for TCD, 0.56-5.74μg kg-1 for TCD-SO, 0.76-9.11μg kg-1 for TCD-SO2, and 0.94-24.02μg kg-1 for Kato-TCD, respectively. Lastly, the assay was further applied to detect TCD and its metabolites in real samples and we are satisfied that this AuNP-based LFIA is a useful tool for the rapid and sensitive screening of TCD medicines in foodstuff samples.