Flame Ionization Gas-Liquid Chromatographic Determination of Antioxidants in Vegetable Oil

Abstract

Abstract A procedure is described which is suitable for the analysis of the 2 isomers of butylated hydroxyanisole, butylated hydroxy toluene, monotert- butylhydroquinone, n-propyl gallate, and nordihydroguaiaretic acid. The method described is sensitive to 0.05 ng. The antioxidants are extracted from n-hexane with acetonitrile and 80% ethanol. Butylated hydroxytoluene is eluted from Florisil (3% deactivated) with n-hexane saturated with acetonitrile and containing 2% ethanol. Quantitation of the antioxidants is performed by gas chromatographic analysis of the trimethylsilyl derivatives, using methyl pentadecanoate as the internal standard. Identity is confirmed by thin layer chromatography, employing the 2-dimensional solvent system described by Sahasrabudhe. Recoveries range from 67 to 100%.