A high sensitive platinum-modified colloidal gold immunoassay for tenuazonic acid detection based on monoclonal IgG

Due to the threat of tenuazonic acid (TA) to public health, it is urgent to establish rapidly effective and sensitive assay methods for TA. In this study, a TA-specific IgG monoclonal antibody (McAb) with high affinity (Kaff was 1.72 x 1010 L/mol) was screened, and the developed icELISA for TA detection has IC50 of 2.50 ng/mL and LOD of 0.17 ng/mL. Platinum-modified gold nanoparticle (Au@PtNP) was optimized as Au@Pt0.4NP, and the resulted Au@Pt0.4NP-McAb probe was designed to catalyze precipitation-type tetramethylbenzidine for visual detection of trace TA with visual LOD of 0.39 ng/mL. The sensitivity of this established Au@Pt0.4NP-McAb strip was highly increased when compared with the existing colloidal gold strip. The developed strip was used to detect trace TA in apple juice and tomato ketchup which were consistent with the results from UHPLC-MS/MS. Therefore, this developed strip could be used for rapid detection of trace TA in real samples.

Automated summary

A specific IgG monoclonal antibody for TA detection was developed in this study, along with an icELISA assay and a visual detection strip using Au@Pt0.4NP-McAb probe. Detection of trace TA in apple juice and tomato ketchup was consistent with UHPLC-MS/MS results, showing increased sensitivity compared to existing methods.