Abstract:

Objective: An indirect competitive time-resolved fluoroimmunoassay (TRFIA) was established using anti-DON polyclonal antibody and coating antigen DON-BSA to detect deoxynivalenol in cereal. Methods: In an indirect TRFIA format, DON-BSA was coated onto a 96-well microplate and incubated with standard DON and DON polyclonal antibody, and a goat anti-rabbit IgG-Eu3+ conjugate was then used to evaluate the methodology of DON-TRFIA. Results: The IC50 value was 4.84 ng/ml at a practical working concentration ranging from 0.01 to 100 ng/ml and the sensitivity for detection was 0.01 ng/ml. Both intra- and inter-assay standard deviations were less than 10%. The half-life time of reagents in assay was over 6 months at 4 ℃. The recovery rates of deoxynivalenol in spiked wheat, corn, beer and bread were 89.41%－123.2%, 115.6%－123.6%, 80.35%－118.0% and 87.00%－92.45%, respectively. Additional analysis for corn samples confirmed that determination results using TRFIA method were in good agreement with those using ELISA method. Conclusion: The TRFIA method has the highest sensitivity for quantitatively analyzing DON in cereal and reveals excellent promising.

Key words: deoxynivalenol, time-resolved fluoroimmunoassay, biotoxin