Faculty of Engineering Hunedoara, "Politehnica" University of Timisoara, Romania.
Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD 20740, USA.
J Chromatogr A. 2014 Jan 10;1324:238-41. doi: 10.1016/j.chroma.2013.11.033. Epub 2013 Nov 22.
Specifications in the U.S. Code of Federal Regulations for the color additive D&C Green No. 8 (Colour Index No. 59040) limit the levels of the subsidiary colors 1,3,6-pyrenetrisulfonic acid trisodium salt (P3S) and 1,3,6,8-pyrenetetrasulfonic acid tetrasodium salt (P4S). The present paper describes a comparative study of two possible methods to replace the currently used multi-step TLC/spectrophotometry method of separating and quantifying the minor components P3S and P4S in G8. One of the new approaches uses conventional high-performance liquid chromatography (HPLC) and the other, derivative spectrophotometry. While the derivative spectrophotometric method was shown to be inadequate for the analysis of minor components overwhelmed by components of much higher concentration, the HPLC method was proven highly effective. The closely related, very polar compounds P3S and P4S were separated by the new HPLC method in less than 4 min using a conventional HPLC instrument. P3S and P4S were quantified by using five-point calibration curves with data points that ranged from 0.45 to 7.63% and from 0.13 to 1.82%, by weight, for P3S and P4S, respectively. The HPLC method was applied to the analysis of test portions from 20 batches of D&C Green No. 8 submitted to the U.S. Food and Drug Administration for certification.
美国联邦法规中的颜色添加剂 D&C 绿 No.8（索引号 59040）的规格限制了次色 1,3,6-苝三磺酸三钠盐（P3S）和 1,3,6,8-苝四磺酸四钠盐（P4S）的含量。本文描述了两种可能的方法的比较研究，以取代目前用于分离和定量 G8 中次要成分 P3S 和 P4S 的多步 TLC/分光光度法。其中一种新方法使用常规高效液相色谱法（HPLC），另一种方法是导数分光光度法。虽然导数分光光度法不适用于被浓度高得多的成分淹没的次要成分的分析，但 HPLC 方法被证明非常有效。用新的 HPLC 方法，在不到 4 分钟的时间内，即可分离出具有高度极性的相关化合物 P3S 和 P4S。用五点校准曲线法对 P3S 和 P4S 进行定量分析，P3S 和 P4S 的校准曲线范围分别为 0.45 至 7.63%和 0.13 至 1.82%（重量）。该 HPLC 方法应用于美国食品和药物管理局认证的 20 批 D&C 绿 No.8 的测试部分分析。
