A new instrument that bridges the gap between gas chromatography (GC) and liquid chromatography (LC) mass spectrometry (MS) was developed. In this instrument GC-MS and electron ionization LC-MS were combined in one MS system with method based mode changing. The LC pneumatic spray formation interface to MS was mounted on top of an otherwise unused GC detector slot and was connected with a flow restriction capillary to the MS through the GC oven and into the MS transfer line, parallel to the GC capillary column. The LC output mobile phase flow is directed into a spray formation and vaporization chamber. The pneumatic spray results in fine spray droplets that are thermally vaporized at a pressure equal to or greater than ambient. A portion of the vaporized mixture is directed into the heated flow restriction capillary that connects the spray formation and vaporization chamber into the electron ionization (EI) ion source, while most of the vaporized spray is released to the atmosphere. The combined GC-MS and LC-MS system can work either with standard EI or with cold EI via interfacing the flow restriction capillary into a supersonic nozzle forming a supersonic molecular beam of a vibrationally cold sample compound. We found that EI-LC-MS with cold EI has many benefits when compared with standard EI. The EI-LC-MS interface can also serve for flow injection analysis. The performance of the combined system is demonstrated in the analysis of a few sample mixtures by both GC-MS and LC-MS analysis, sequentially without hardware adjustments.

中文翻译：

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在一个系统中同时进行液相色谱和气相色谱的电子电离质谱分析，无需进行硬件调整。


开发了一种弥合气相色谱 (GC) 和液相色谱 (LC) 质谱 (MS) 之间差距的新仪器。在该仪器中，GC-MS 和电子电离 LC-MS 结合在一个 MS 系统中，并具有基于方法的模式改变。 MS 的 LC 气动喷雾形成接口安装在未使用的 GC 检测器插槽的顶部，并通过限流毛细管通过 GC 炉箱连接到 MS，并连接到与 GC 毛细管柱平行的 MS 传输线。 LC 输出流动相流被引导至喷雾形成和汽化室。气动喷雾产生细小的喷雾液滴，这些液滴在等于或大于环境压力的压力下热汽化。一部分汽化混合物被导入加热的限流毛细管，该毛细管将喷雾形成和汽化室连接到电子电离 (EI) 离子源，而大部分汽化喷雾则释放到大气中。 GC-MS 和 LC-MS 组合系统可以与标准 EI 一起工作，也可以通过将限流毛细管连接到超音速喷嘴中来与冷 EI 一起工作，从而形成振动冷样品化合物的超音速分子束。我们发现，与标准 EI 相比，采用冷 EI 的 EI-LC-MS 有许多优点。 EI-LC-MS 接口还可用于流动注射分析。组合系统的性能通过 GC-MS 和 LC-MS 分析对一些样品混合物的分析得到了证明，无需硬件调整。