Franchina Flavio A, Maimone Mariarosa, Tranchida Peter Q, Mondello Luigi
Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, University of Messina, Polo Annunziata, viale Annunziata, 98168 Messina, Italy.
Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, University of Messina, Polo Annunziata, viale Annunziata, 98168 Messina, Italy; Università Campus Bio-Medico of Rome, via Álvaro del Portillo, 21, 00128 Rome, Italy; Chromaleont s.r.l., c/o University of Messina, Polo Annunziata, viale Annunziata, 98168 Messina, Italy.
J Chromatogr A. 2016 Apr 8;1441:134-9. doi: 10.1016/j.chroma.2016.02.041. Epub 2016 Feb 16.
The main objective of the herein described research was focused on performing satisfactory flow modulation (FM), in comprehensive two-dimensional gas chromatography-mass spectrometry (GC×GC-MS), using an MS-compatible second-dimension gas flow of approx. 4 mL min(-1). The FM model used was based on that initially proposed by Seeley et al. [3]. The use of limited gas flows was enabled through fine tuning of the FM parameters, in particular the duration of the re-injection (or flushing) process. Specifically, the application of a long re-injection period (i.e., 700 ms) enabled efficient accumulation-loop flushing with gas flows of about 4 mL min(-1). It was possible to apply such extended re-injection periods by using different restrictor lengths in the connections linking the modulator to the auxiliary pressure source. FM GC×GC-MS applications were performed on a mixture containing C9-10 alkanes, and on a sample of essential oil. GC×GC-MS sensitivity was compared with that attained by using conventional GC-MS analysis, in essential oil applications. It was observed that signal intensities were, in general, considerably higher in the FM GC×GC-MS experiments.
本文所述研究的主要目标是，在全二维气相色谱-质谱联用仪（GC×GC-MS）中，使用约4 mL min⁻¹的与质谱兼容的第二维气流，实现令人满意的流量调制（FM）。所使用的FM模型基于Seeley等人[3]最初提出的模型。通过对FM参数进行微调，特别是再进样（或冲洗）过程的持续时间，得以使用有限的气流。具体而言，应用较长的再进样时间（即700 ms）能够在约4 mL min⁻¹的气流下实现有效的累积环冲洗。通过在连接调制器与辅助压力源的连接处使用不同长度的限流器，可以应用这种延长的再进样时间。FM GC×GC-MS应用于含有C9 - 10烷烃的混合物以及精油样品。在精油应用中，将GC×GC-MS的灵敏度与使用传统GC-MS分析所获得的灵敏度进行了比较。结果发现，在FM GC×GC-MS实验中，信号强度总体上要高得多。
