Use of a recently-developed thermal modulator within the context of comprehensive two-dimensional gas chromatography combined with time-of-flight mass spectrometry: Gas flow optimization aspects.

The present research is based on the use of a recently-developed comprehensive two-dimensional gas chromatography thermal modulator, defined as solid state modulator. The transfer device was installed on top of a single GC oven, while benchtop low-resolution time-of-flight mass spectrometry was used to monitor the compounds exiting the second analytical column. The solid state modulator was first described in 2016 by Luong et al. (Anal. Chem. 2016, 88, 8428-8432), and is a moving modulator which does not require heating and cooling gases to generate comprehensive two-dimensional GC data. The accumulation and re-mobilization steps occur on a trapping capillary, this being subjected to thermoelectric cooling and micathermic heating. In the present research, the effects of the gas linear velocity on the modulation performance, were evaluated by using two different uncoated trapping capillaries, viz., 0.8 m × 0.25 mm id and 0.8 m × 0.20 mm id. Solid state modulator applications were carried out on a standard solution containing n-alkanes (C9, C10, C12 ), and on a sample of diesel fuel. The results indicated that the type of trapping capillary and gas velocity have a profound effect on modulation efficiency. This article is protected by copyright. All rights reserved.