PREPARATION AND CHARACTERIZATION OF AFLATOXIN B2a-HEMIGLUTARATE AND ITS USE FOR THE PRODUCTION OF ANTIBODY AGAINST AFLATOXIN B1

Hemisuccinate (HS) and hemiglutarate (HG) of aflatoxin B_2a (afla B_2a) were prepared by refluxing afla B_2a with the corresponding anhydride and 4-N, N-dimethylaminopyridine in tetrahydrofuran. Two epimers of the respective HS or HG which show different chromatographic behavior and physiochemical properties were isolated and characterized. Afla B_2a-HS hydrolyzes very rapidly in aqueous solution and was not used for further study. Afla B_2a-HG hydrolyzes at a much slower rate and was selected for the coupling to protein. Using the mixed anhydride method, as much as 12 moles of afla B_2a-HG were conjugated to each mole of bovine serum albumin (BSA). The antibody obtained from rabbits immunized with afla B_2a-HG BSA is most specific to afla B₁ and shows little cross reaction with afla G₁ and aflatoxicol. The lower limit for detection of afla B₁ by radioimmunoassay using this antibody is in the range of 30–50 pg per assay.