Instrumental HPTLC of Aflatoxins: Fluorescence Enhancement by Corn Free Fatty Acids

Abstract

Greater than 100% recoveries using instrumental HPTLC were observed for aflatoxin (AFT) analysis in spiked corn samples. I₂ detection of spots over-laying AFT B₁ and B₂ were identified by GLC as C₁₆ ^−c18 free fatty acids (FFA). These FFA were found to enchance the fluorescence of AFT B₁ from 13.7% to 35.7% greater than controls resulting in >100% recoveries. The inclusion of glacial acetic acid in the TLC mobile phase resulted in an increased mobility of the FFA which eliminated the positive interference on AFT fluorescence. Recoveries using the modified developing solvent then gave values in acceptable ranges.