高效液相色谱法检测面粉中的乙二胺四乙酸二钠

Determination of ethylenediaminetetraacetic acid disodium in flour by high performance liquid chromatography

中文关键词:  高效液相色谱法  乙二胺四乙酸二钠  面粉  食品添加剂

英文关键词:high performance liquid chromatography  ethylenediaminetetraacetic acid disodium  flour  food additive

中文摘要:

      目的 建立一种高效液相色谱法检测面粉中乙二胺四乙酸二钠(ethylenediaminetetraacetic acid disodium, EDTA-2Na)的分析方法。方法 样品经水超声提取后, 通过EDTA与铜离子(Cu2+)的螯合作用, 采用高效液相色谱法, 以Dikma C18柱(250 mm×4.6 mm, 5 μm)为色谱柱, 柱温30 ℃、流速1.0 mL/min、检测波长254 nm, 以水(含有0.02 mol/L四丁基溴化铵, 0.03 mol/L乙酸钠缓冲液, pH=4):甲醇(80:20, V:V)为流动相, 对EDTA-2Na进行测定。通过铋离子(Bi3+)对面粉中的EDTA-2Na进行确证。结果 该方法线性范围为20~400 μg/mL, 相关系数为0.9995, 检出限为10 mg/kg (S/N=3), 加标回收率为95.8%~99.8%, RSD为1.3%~2.2%。结论 该方法对面粉中的EDTA-2Na进行了有效的检测和确证, 用铋离子(Bi3+)溶液作为确证试剂, 相对于传统方法中用铁离子(Fe3+), 具有更高的专属性, 结果更加准确可靠, 可作为面粉中EDTA-2Na的检测方法。

英文摘要:

      Objective To establish a method for determination of ethylenediaminetetraacetic acid disodium (EDTA-2Na) in flour by high performance liquid chromatography (HPLC). Methods Analytes in the flour samples were extracted by sonication method. Copper ion with EDTA was formed in order to be determined by HPLC. The separation was carried out using a Dikma C18 column (250 mm×4.6 mm, 5 μm) and the temperature was maintained at 30 ℃. The mobile phase consisting of water: methanol (80:20, V:V) was prepared by addition of tetrabutyl ammonium bromide (0.02 mol/L) and sodium acetate trihydrate (0.03 mol/L) followed by pH adjusted to 4.0 with phosphoric acid. The flow rate was optimized to 1.0 mL/min consideration of the resolution (2.0) and efficiency. Results The linearity range of this method was from 20 to 400 μg/mL with a correlation coefficient of 0.9995. The limit of detection (LOD) of copper(II) ethylenediaminetetraacetic acid was 10 mg/kg (S/N=3), and the recoveries from spiked samples were 95.8%~99.8%, and RSD were 1.3%~2.2%. Conclusion To make the results more reliable, bisthum ion (Bi3+) reagent is selected as a substitution of ferric ion (Fe3+) to distinguish EDTA in flour. The method has been proved to be simple and sensitive and can be used as a reference method for determination of EDTA-2Na in flour.