Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
J Chromatogr A. 2012 Feb 10;1224:61-9. doi: 10.1016/j.chroma.2011.12.046. Epub 2011 Dec 19.
Two-dimensional liquid chromatography (2-D LC) has been widely used for the analysis of complex samples owing to its great improvement in separation selectivity and peak capacity. However, one 2-D LC system may not be enough to meet the separation requirements due to the complexity of certain samples and respective limitations of two separation modes. In this work, water extract of Scutellaria barbata D. Don, a traditional Chinese medicine, was fractionated into polar fraction and medium-polar fraction by means of solid phase extraction (SPE). The fraction preparation made it easy to select the corresponding combination of 2-D LC method from hydrophilic interaction chromatography (HILIC) and reversed-phase liquid chromatography (RP-LC). An off-line 2-D HILIC×HILIC to analyze the polar fraction and an off-line 2-D HILIC×RP-LC to analyze the medium-polar fraction were developed, respectively. In total, 749 peaks were detected: 206 peaks from the polar fraction by the 2-D HILIC×HILIC and 543 from the medium-polar fraction by the 2-D HILIC×RP-LC. The practical peak capacities obtained in both systems were 2698 and 2879, and the orthogonality reached 63.18% and 90.62%, respectively. The results demonstrated that the two systems were both highly orthogonal, and the peak capacities greatly increased.
二维液相色谱（2-D LC）由于其在分离选择性和峰容量方面的巨大提高，已被广泛用于分析复杂样品。然而，由于某些样品的复杂性和两种分离模式各自的局限性，一个 2-D LC 系统可能不足以满足分离要求。在这项工作中，采用固相萃取（SPE）法将黄芩的水提取物分为极性部分和中等极性部分。通过部分制备，很容易从亲水相互作用色谱（HILIC）和反相液相色谱（RP-LC）中选择相应的 2-D LC 方法组合。分别开发了离线 2-D HILIC×HILIC 用于分析极性部分和离线 2-D HILIC×RP-LC 用于分析中等极性部分。总共检测到 749 个峰：2-D HILIC×HILIC 从极性部分得到 206 个峰，2-D HILIC×RP-LC 从中等极性部分得到 543 个峰。两个系统的实际峰容量分别为 2698 和 2879，正交度分别达到 63.18%和 90.62%。结果表明，两个系统均具有高度正交性，并且峰容量大大增加。
