邻二氮菲-Fe3+法测定保健食品中水溶性成分的抗氧化能力

目的：建立用邻二氮菲-Fe3+测定保健食品中水溶性成分抗氧化能力的方法。方法：用水相提取保健食品中的水溶性抗氧化成分，使其还原反应体系中的Fe3+，生成的亚铁离子与邻二氮菲反应成稳定的橙红色络合物，用分光光度计在536nm波长处测定吸光度。以水溶性VE为对照，由此计算样品水溶性成分中抗氧化(还原性)物质的多少。通过对方法线性关系、最低检测限、精密度、准确度等指标进行测定，验证方法的可行性。结果：检测Trolox在质量浓度0.66～10.53μmol/L范围内呈现良好的线性关系(R2=0.9999)；最低检测下限为0.54μmol /L；平行性精密度为2.7%；重复性精密度为3.3%；5次重复加标回收率为(99.9±4.6)%。结论：邻二氮菲-Fe3+法可用于保健食品中水溶性成分抗氧化能力的检测。

Determination of Antioxidant Capacity of Water-soluble Compounds in Functional Food by Phenanthroline-Ferric Ion Method

Objective: To establish a colorimetric method to determine the antioxidant capacity of water-soluble compounds in functional food based on the reaction between 1,10-2 phenanthroline and Fe3+ to form yellow complexes.Methods: The hydrophilic antioxidants in functional foods were extracted with pH 7.4 PBS buffer solution(75 mmol/L) and allowed to reduce Fe3+ to Fe2+.Fe2+ was exposed to 1,10-2 phenanthroline to form a stable Fe2+-phenanthroline complex.The absorbance of the complex was determined on a spectrop...