Online two-dimensional (2D) comprehensive liquid chromatography (LC × LC) has become increasingly popular. Most LC × LC separations employ one or more detectors at the outlet of the second dimension, ²D, with very short runs to avoid undersampling. We used six detectors, including dual parallel mass spectrometry (LC1MS2), for detection of the first dimension, ¹D. We made an argentation (silver-ion) UHPLC column from a strong cation exchange column for ²D, coupled with UV and LC1MS2 detection. LC1MS2 in ¹D combined with LC1MS2 in ²D, plus five other detectors, constituted LC2MS4 in a comprehensive LC1MS2 × LC1MS2 2D-LC separation. Electrospray ionization (ESI) high resolution accurate mass (HRAM) mass spectrometry (MS) and atmospheric pressure chemical ionization (APCI) MS were used in parallel for ¹D detection, while atmospheric pressure photoionization (APPI) MS and ESI-MS were used for detection of ²D. The LC1MS2 used for ¹D allowed quantification of triacylglycerol (TAG) molecular species of Parinari curatellifolia and other seed oils, while the ²D allowed isomers of TAG containing 18:3 fatty acyl chains as well as TAG regioisomers to be separated and identified. The LC1MS2 in ¹D allowed identification of oxo-TAG species by HRAM MS and quantification of 806.3 ± 1.3 and 1101 ± 22 μg/g of α- and γ- tocopherols, respectively, in P. curatellifolia by APCI-MS. It is now feasible to use silver-ion UHPLC as the ²D separation in LC × LC and to use multiple mass spectrometers across both dimensions to perform conventional quantitative analysis and to take advantage of the newest LC × LC separation technology to identify isomers that are otherwise difficult to separate.

中文翻译：

---

全面的双重液相色谱和四重质谱（LC1MS2×LC1MS2 = LC2MS4），用于分析伞形姜黄和其他种子油中的三酰甘油

在线二维（2D）综合液相色谱（LC×LC）变得越来越流行。大多数LC×LC分离器在第二维² D的出口处使用一个或多个检测器，并且运行时间非常短，以避免欠采样。我们使用了六个检测器，包括双平行质谱（LC1MS2），用于检测的第一尺寸的，¹ D.我们从一个强阳离子交换柱由argentation（银离子）UHPLC柱为² d，加上UV和LC1MS2检测。LC1MS2在¹ d与LC1MS2组合²D，再加上其他五个检测器，在全面的LC1MS2×LC1MS2 2D-LC分离中组成了LC2MS4。电喷雾电离（ESI）高分辨率精确质量（HRAM）质谱（MS）和大气压化学电离（APCI）MS中用于并行使用^1次d检测，而大气压光电离（APPI）MS和ESI-MS被用于检测²用于d的LC1MS2 ¹三酰甘油（TAG）的d允许定量的分子种类Parinari curatellifolia和其他种子油，而² TAG的d允许异构体含有18：3脂肪酸的酰基链以及TAG区域异构体为分开并确定。LC1MS2合¹d允许通过HRAM MS鉴定氧代TAG物种的和定量的806.3±1.3和1101±22微克α-和γ-生育酚，分别在中/克P. curatellifolia通过APCI-MS。现在是可行的使用银离子UHPLC作为²在LC×LC d分离和使用多个质谱仪在两个维度来执行常规定量分析，并利用最新的LC×LC分离技术，以确定是同分异构体否则很难分开。