oa Application of an SFC-IM-QTOF System to the Detection of Glycerol Dialkyl Glycerol Tetraethers

Glycerol Dialkyl Glycerol Tetraethers (GDGTs) have been used as proxies for environmental studies for the past decades due to their response to environmental parameters and wide distribution. While the most widely used method to analyze them has been shown to produce very reproducible results, the runtime and solvent volume required to run this method makes it burdensome to analyze large arrays of samples, which is a limitation for the application of this proxy in high-resolution paleoreconstructions, where large numbers of samples are required. Here we present the results of implementing a Supercritical Fluid Chromatography coupled to Ion Mobility and quadrupole Time of Flight mass spectrometry (SFC-qTOF) system to measure GDGTs. This method produces results with a comparable distribution of the GDGTs to the classical HPLC-MS method, where the GDGTs are correctly detected. Furthermore, the application of Ion Mobility (IM) provides information about the shape of the ions, which can be used to make inferences about the response mechanism of brGDGTs to the environment. While improvements in this method are still required, the versatility of the SFC-IM-qTOF system could provide a useful tool for the application of GDGTs in paleoreconstructions and a better mechanistic understanding of the proxy.