Submitted to: Analytica Chimica Acta
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/18/2010
Publication Date: 5/25/2010
Citation: Kadota, T., Takezawa, Y., Hirano, S., Tajima, O., Maragos, C.M., Nakajima, T., Tanaka, T., Kamata, Y., Sugita-Konishi, Y. 2010. Rapid detection of nivalenol and deoxynivalenol in wheat using surface plasmon resonance immunoassay. Analytica Chimica Acta. 673:173-178. Interpretive Summary: Nivalenol (NIV) is a trichothecene related to deoxynivalenol (DON, vomitoxin), a mycotoxin commonly found in cereal commodities in the United States. Because NIV has been reported to occur frequently in Asia and Europe, it is of concern there, in particular because of the suggestion that NIV may be more toxic than DON. For this reason rapid and sensitive methods for detecting NIV and DON are important. This report describes a novel antibody-based biosensor using surface plasmon resonance for the detection of NIV and DON in wheat. Because the sensor can detect both toxins it may be highly useful in areas where these toxins may co-occur.
Technical Abstract: Surface plasmon resonance immunoassay using a monoclonal antibody was developed to measure nivalenol (NIV) and deoxynivalenol (DON) contamination in wheat. A DON-immobilized sensor chip having high sensitivity and stability was prepared, and an SPR detection procedure was developed. The competitive inhibition assay used a monoclonal antibody that cross-reacts with NIV and DON. The half maximal inhibitory concentration (IC50) values of the SPR assay were 28.8 and 14.9 ng/ml for NIV and DON, respectively. Simultaneous detection of both NIV and DON in wheat was achieved by including a simple cleanup procedure. Additionally, NIV and DON were measured independently after separating them using a commercial immunoaffinity column (IAC). The spiked toxins were recovered in the range of 91.5 - 107 % with good relative standard deviations (RSDs) of 0.40 - 4.1 %, and the detection limits were 0.1 and 0.05 mg/kg for NIV and DON, respectively. In the case of independent detection using IAC, detection limits were 0.2 and 0.1 mg/kg for NIV and DON. SPR analysis of contaminated wheat samples correlated with a conventional LC/MS/MS method. The developed SPR assay is a practical method for rapid screening of NIV and DON, and is one of only a few immunoassays to detect NIV directly.