Choice of procedure conditions for radioimmunoassay of aflatoxin B1 using125I as a marker and dextrancoated charcoal as a separation matrix

Abstract

Assay conditions for the radioimmunoassay for aflatoxin B1 using125I-radiolabel and dextran-coated charcoal for the separation of free and bound radioligand were optimized. Casein was chosen as the best protecting protein /in contrast with human serum albumin, γ-globulin and gelatine/. The most suitable incubation conditions are at 4°C for 18 h in darkness, radioligand sorption on the dextrancoated charcoal takes place 30 min at 4°C and the antiserum is diluted in order to reach zero specific binding in the range between 35 and 50%.