Development of indirect competitive ELISA and lateral-flow immunochromatographic assay strip for the detection of sterigmatocystin in cereal products

Sensitive and specific anti-sterigmatocystin (STG) monoclonal antibody (mAb) 4G10 was obtained by immunization and cell fusion. An indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) method and lateral-flow immunochromatographic assay (ICA) strip method were developed for the detection of STG in cereal products based on this mAb. The 50% inhibition concentration and limit of detection for the ic-ELISA method were 0.092 and 0.015ng/mL, respectively. The visual limit of detection (vLOD) and cut-off value for the lateral-flow ICA strip method were 0.1 and 0.5ng/mL, respectively. From the analysis of different cereal samples (wheat, maize and rice), the recovery rates ranged from 78.3% to 122.0% for the ic-ELISA method. For the lateral-flow ICA strip, the vLODs were 3, 1.2 and 3ng/g, and the cut-off values were 12, 6 and 6ng/g for wheat, maize and rice, respectively. Therefore, both of the developed methods are suitable for the on-site detection and rapid screening of numerous samples.