Effect of Reaction Format on a McAb-Based Heterologous ELISA for the Insecticide Parathion

Abstract

Based on the selected monoclonal antibody, the effect of three reaction formats on sensitivity, specificity, and determination ability for real samples were investigated. The results showed the antibody-coated format was the optimal assay for parathion determination. The sensitivity of the assay was 3.20 ng/ml, with a detection limit of 0.40 ng/ml, and the assay time was 1.5 h. The average recoveries of parathion in river water, rice, cucumber, green soy bean, and cabbage were 98.56%, 89.46%, 99.25%, 118.57%, and 101.39%, respectively. In addition, when rice and cabbage extracts were analyzed by the assay and HPLC, the correlation was greater than 0.9.

Keywords:

• Enzyme-linked immunosorbent assay (ELISA)
• parathion
• reaction format

This work was supported by the National Natural Science Foundation of China (30370944) and the Specialized Research Fund for the Doctoral Program of Higher Education.

Notes

N: no competitive reaction happened.

^a IC₅₀ value could not be determined accurately due to the limited solubility at high concentrations; however, it was clear that inhibition was less than 50% at 10000 ng/ml.