Competitive Elisa for quantifying small Amounts of aflatoxin B1

Abstract

An indirect ELISA was developed to quantify aflatoxin B₁ (AFB₁). The detection limit was 0.025 ng ml^‐1. The test used polyvinyl chloride (PVC) plates, activated with AFB₁ bound to bovine serum albumin (BSA). Polyclonal antibodies were raised in rabbits against AFB₁‐BSA. The specific anti‐AFB₁antibodies 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 IgG anti‐AFB₁ 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 AFB₁. Cross‐reactivity with aflatoxin B₂, aflatoxin G₁ and aflatoxin G₂ was measured, showing percentages of 5.43, 64.5 and 5.07 respectively.