Competitive ELISA for quantifying small amounts of aflatoxin B-1

An indirect ELISA was developed to quantify aflatoxin B-1 (AFB(1)). The detection limit was 0.025 ng ml(-1). The test used polyvinyl chloride (PVC) plates, activated with AFB(1) bound to bovine serum albumin (BSA). Polyclonal antibodies were raised in rabbits against AFB(1)-BSA. The specific anti-AFB(1) antibodies were recovered from the crude antiserum by affinity chromatography from a column containing immobilized BSA on Nylon 6-6. Goat anti-rabbit IgG antibodies bound to peroxidase were used to detect the rabbit Ige anti-AFB(1) antibodies bound to PVC plates. The colour developed by the subsequent enzyme conversion of the substrate was detected by spectrophotometry. The developed colour gave clear absorbance differences at varying doses of AFB(1). Cross-reactivity with aflatoxin B-2, aflatoxin G(1) and aflatoxin G(2) was measured, showing percentages of 5.43, 64.5 and 5.07 respectively.