Savareear Benjamin, Jacobs Matthew R, Shellie Robert A
Australian Centre for Research on Separation Science (ACROSS), University of Tasmania, Private Bag 75, Hobart 7001, Australia.
Australian Centre for Research on Separation Science (ACROSS), University of Tasmania, Private Bag 75, Hobart 7001, Australia.
J Chromatogr A. 2014 Oct 24;1365:183-90. doi: 10.1016/j.chroma.2014.09.014. Epub 2014 Sep 16.
A multiplexed dual-primary column comprehensive two-dimensional gas chromatography-mass spectrometry approach (2GC×GC-MS) is introduced. The approach splits injected samples into two first-dimension columns with different stationary phases, and recombines the two streams into one second-dimension column that terminates at a single detector. The approach produces two two-dimensional chromatograms for each injection, and is made possible by using a dual-stage modulator operated in contra-directional modulation mode. The dual two-dimensional chromatograms produced by this single detector system provide complementary information due to selectivity differences between the three separation columns used in the column ensemble. An aged Australian tea tree (Melaleuca alternifolia) essential oil was analyzed to demonstrate the 2GC×GC-MS approach. The number of compounds separated by each of the GC×GC separations in the 2GC×GC experiment is comparable to conventional GC×GC experiments with matching column configurations. Robust peak assignment was possible for this sample based on the combination of MS library matches and multiple linear retention index searching. Forty-nine components (22 unique) were identified using a non-polar×mid-polar column combination and 34 components (7 unique) were positively identified using a polar×mid-polar column combination. Twenty-seven peak assignments were corroborated by positive identification in both of the multiplexed separations.
介绍了一种多路复用双初级柱全二维气相色谱 - 质谱联用方法（2GC×GC-MS）。该方法将注入的样品分流到两根具有不同固定相的一维柱中，然后将这两股流重新合并到一根终止于单个检测器的二维柱中。该方法每次进样会产生两张二维色谱图，这通过使用以反向调制模式运行的双级调制器得以实现。由于柱组中使用的三根分离柱之间的选择性差异，这个单检测器系统产生的两张二维色谱图提供了互补信息。分析了一种陈化的澳大利亚茶树（互叶白千层）精油以展示2GC×GC-MS方法。在2GC×GC实验中，每次GC×GC分离所分离出的化合物数量与具有匹配柱配置的传统GC×GC实验相当。基于质谱库匹配和多重线性保留指数搜索的组合，对该样品进行可靠的峰归属是可行的。使用非极性×中极性柱组合鉴定出49种成分（22种独特成分），使用极性×中极性柱组合明确鉴定出34种成分（7种独特成分）。在两种多路复用分离中，有27个峰的归属通过阳性鉴定得到了证实。
