A rapid ELISA for screening aflatoxin B1 in animal feed and feed ingredients in Indonesia

Abstract

To facilitate a sustainable aflatoxin management system in Indonesia, a simple, rapid and effective Enzyme Linked Immunosorbent Assay (ELISA) test for screening aflatoxin B1 (AFB1) in animal feed and feed ingredients was developed. Anti-AFB1 polyclonal antibodies were produced against AFB1-BSA and AFB1-KLH immunogens. Using AFB1 conjugated to horseradish peroxidase (HRP) as an enzyme marker in a direct competitive ELISA, an IC50 of 0.85±0.15 μg/kg and a detection limit (IC15) of 0.18±0.06 μg/kg of AFB 1 were achieved. The assay was highly specific to AFB1 with very little cross reaction with other aflatoxin congeners (AFB2 0.9%, AFG1 3.1% and AFG2 1.2%) and metabolites. The ELISA was tolerant to methanol (up to 60%) and pH (pH 7.2-9.6) without significantly affecting the overall performance and was not affected by interferences from the animal feed and corn samples. Satisfactory recovery results were obtained from the spike and recovery study (77-97% recovery for 10-252 μg/kg). A pilot survey conducted on corn and animal feed samples collected from the local feed factories and poultry shops indicated that significant amounts of corn and animal feeds were contaminated by aflatoxin B1 greater than the MRL (50 μg/kg). © 2006 Taylor & Francis.