Simultaneous analysis of Vitamins A and E in infant milk-based formulae by normal-phase high-performance liquid chromatography-diode array detection using a short narrow-bore column

A rapid, simple and reproducible normal-phase (NP) high-performance liquid chromatography (HPLC)-diode array detection (DAD) method for simultaneous qualitative and quantitative determination of Vitamin A (retinol acetate and retinol palmitate) and Vitamin E (alpha-tocopherol acetate, alpha-, gamma- and delta-tocopherols) in milk-based infant formulae was developed and validated. The preparation sample was based on protein precipitation and vitamin extraction with ethanol, followed by re-extraction with hexane, while the chromatographic method was based on the use of a short narrow-bore column (50 mm x 2.1 mm; 3 mu m particle size), which afforded less solvent consumption and higher mass sensitivity. The method showed acceptable values for precision, recovery and sensitivity, and proved very simple for routine analysis work. (c) 2006 Elsevier B.V. All rights reserved.