Chase G W, Eitenmiller R R, Long A R
U.S. Food and Drug Administration, Atlanta Center for Nutrient Analysis, GA 30309, USA.
J AOAC Int. 1999 Jan-Feb;82(1):107-11.
A liquid chromatographic method is described for analysis of all-rac-alpha-tocopheryl acetate and retinyl palmitate in medical food. The vitamins are extracted from medical food without saponification by matrix solid-phase dispersion and chromatographed by normal-phase chromatography with fluorescence detection. Retinyl palmitate and all-rac-alpha-tocopheryl acetate are quantitated isocratically with a mobile phase of 0.125% (v/v) and 0.5% (v/v) isopropyl alcohol in hexane, respectively. Results compared favorably with label declarations on retail medical foods. Recoveries determined on an analyte-fortified zero reference material for a milk-based medical food averaged 98.3% (n = 25) for retinyl palmitate spikes and 95.7% (n = 25) for all-rac-alpha-tocopheryl acetate spikes. Five concentrations were examined for each analyte, and results were linear (r2 = 0.995 for retinyl palmitate and 0.9998 for all-rac-alpha-tocopheryl acetate) over the concentration range examined, with coefficients of variation in the range 0.81-4.22%. The method provides a rapid, specific, and easily controlled assay for analysis of retinyl palmitate and all-rac-alpha-tocopheryl acetate in fortified medical foods.
本文描述了一种用于分析医用食品中全消旋α-生育酚醋酸酯和视黄醇棕榈酸酯的液相色谱方法。通过基质固相分散法从医用食品中提取维生素，无需皂化，然后采用正相色谱法和荧光检测进行色谱分析。视黄醇棕榈酸酯和全消旋α-生育酚醋酸酯分别在含0.125%（v/v）和0.5%（v/v）异丙醇的己烷流动相中进行等度定量分析。结果与零售医用食品上的标签声明相符。在一种基于牛奶的医用食品的分析物强化零参考物质上测定的回收率，视黄醇棕榈酸酯加标平均为98.3%（n = 25），全消旋α-生育酚醋酸酯加标平均为95.7%（n = 25）。对每种分析物检测了五个浓度，在所检测的浓度范围内结果呈线性（视黄醇棕榈酸酯的r2 = 0.995，全消旋α-生育酚醋酸酯的r2 = 0.9998），变异系数在0.81 - 4.22%范围内。该方法为强化医用食品中视黄醇棕榈酸酯和全消旋α-生育酚醋酸酯的分析提供了一种快速、特异且易于控制的检测方法。
