Matteo Spedicatoa, Felina Hildebrandb,c, Alberto Cavazzinia, Martina Catania, Gunda Koellenspergerb

aDept. of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, 44121, Ferrara (Italy)
bUniversity of Vienna, Faculty of Chemistry, Department of Analytical Chemistry, 1090 Vienna (Austria)
cVienna Doctoral School in Chemistry (DoSChem), University of Vienna, 1090 Vienna (Austria)

Metabolomics, a rapidly evolving field, provides profound insights into the quantitative and qualitative assessment of metabolites across various domains, including medicine, environment, nutrition, and agriculture. This scientific discipline facilitates global identification of metabolites, offering crucial insights into metabolic profiles and biomarker discovery. Metabolomics analysis is pivotal in comprehending biological processes and human diseases, demanding advanced analytical methodologies to unravel the complexity of the metabolome. Integration of semi-targeted methodologies, such as the use of internal standards (ISTDs), with untargeted approaches is crucial. This work combines parallel liquid chromatography with high-resolution mass spectrometry (HRMS) as a promising approach to cover metabolites over a wide polarity range in clinical studies such as for detection of leaky gut [1]. The diversity of human metabolites, characterised by a wide range of polarities, also requires the implementation of highly sophisticated liquid chromatography systems. In this regard, the use of parallel chromatography, equipped with two binary pumps, two injectors and two column compartments, is crucial. This approach allows the simultaneous application of two complementary separation techniques: reversed phase chromatography (RP) and hydrophilic interaction chromatography (HILIC). This optimised combination, together with the use of high-resolution mass spectrometry (HRMS), allows maximum metabolite coverage and accurate detection of metabolites with different chemical characteristics. In this work, with the aid of parallel chromatography and the implementation of high-resolution mass spectrometry (HRMS), it was possible to identify a wide range of metabolites in a broad polarity range in patients affected by resistant treatment depression [2]. Moreover, metabolites of different classes were identified by means of semi-targeted approaches through the use of internal standards (ISTDs) or non-targeted approaches through the comparison of experimental data with data in the Human Metabolome Database (HMDB). In conclusion, the integration of semi-targeted methodologies, untargeted approaches and the adoption of advanced liquid chromatography systems represent an effective strategy to address the complexity of the human metabolome, enabling a better understanding of biological processes and the identification of clinically relevant biomarkers.

Keywords: High resolution mass spectrometry, Untargeted, Targeted, Metabolomics, Liquid chromatography

References

1. Camilleri M., Gut 68 (2019), pag. 1516. DOI: 10.1136/gutjnl-2019-318427 

2. Kelly J.R., Kennedy P.J., et al., Front Cell Neuroscience, 9 (2015), 392. DOI: 10.3389/fncel.2015.00392