Determination of vitamin E in animal feedingstuffs by high-performance liquid chromatography

Abstract

A method is given for the determination of vitamin E in animal feeds and pet foods. The sample is saponified with ethanolic potassium hydroxide solution and the vitamin E extracted into light petroleum (boiling range 40–60 °C). This solution is evaporated to dryness under reduced pressure and the residue dissolved in hexane. The concentration of vitamin E in this solution is determined by high-performance liquid chromatography using a silica column and an isooctane–propan-2-ol mixture as the mobile phase. An alternative method using hexane–1,4-dioxane as the mobile phase is also given.