Efficient mapping of lignin depolymerization product pools and quantification of specific monomers through rapid GPC-HPLC-UV/VIS analysis

Tibo De Saegher; Joeri Vercammen; Boyana Atanasova; Kevin M Van Geem; Jeriffa De Clercq; An Verberckmoes; Jeroen Lauwaert

doi:10.1016/j.aca.2023.341738

Efficient mapping of lignin depolymerization product pools and quantification of specific monomers through rapid GPC-HPLC-UV/VIS analysis

Anal Chim Acta. 2023 Oct 16:1278:341738. doi: 10.1016/j.aca.2023.341738. Epub 2023 Aug 17.

Authors

Tibo De Saegher¹, Joeri Vercammen², Boyana Atanasova¹, Kevin M Van Geem³, Jeriffa De Clercq¹, An Verberckmoes¹, Jeroen Lauwaert⁴

Affiliations

¹ Industrial Catalysis and Adsorption Technology (INCAT), Department of Materials Textiles and Chemical Engineering (MaTCh), Ghent University, Valentin Vaerwyckweg 1, 9000, Ghent, Belgium.
² Industrial Catalysis and Adsorption Technology (INCAT), Department of Materials Textiles and Chemical Engineering (MaTCh), Ghent University, Valentin Vaerwyckweg 1, 9000, Ghent, Belgium; Interscience Expert Center (IS-X), Avenue J.E. Lenoir 2, 1384, Louvain-la-Neuve, Belgium.
³ Laboratory for Chemical Technology (LCT), Department of Materials Textiles and Chemical Engineering (MaTCh), Ghent University, Technologiepark 125, 9052, Ghent, Belgium.
⁴ Industrial Catalysis and Adsorption Technology (INCAT), Department of Materials Textiles and Chemical Engineering (MaTCh), Ghent University, Valentin Vaerwyckweg 1, 9000, Ghent, Belgium. Electronic address: Jeroen.Lauwaert@UGent.be.

PMID: 37709433
DOI: 10.1016/j.aca.2023.341738

Abstract

Background: Growing research on lignin depolymerization to functionalized bio-aromatics has necessitated dedicated analysis techniques. However, immense variability in molecular weight and functional groups of the depolymerization products impedes fast analysis of a large number of samples while remaining in-depth enough for catalyst screening or reaction condition optimization. While GPC-HPLC-UV/VIS has been a promising technique, up until now, the information it provides is largely qualitative. By enabling quantification of key monomeric products and through further reduction of overall analysis time, this study aims to increase the potential of GPC-HPLC-UV/VIS for fast and in-depth characterization of lignin depolymerization product pools.

Results: Analysis of selected samples, isolated from GPC-HPLC-UV/VIS analyses of lignin depolymerization product pools, with gas chromatography (GC) equipped with an Orbitrap high-resolution accurate mass spectrometer (Orbitrap-HR/AM-MS) is successful in identifying the main low monomeric products. Moreover, these identifications are further substantiated through GPC-HPLC-UV/VIS analysis of standards. Furthermore, straight forward quantification of these products directly within GPC-HPLC-UV/VIS is successfully developed with limits of detection ≤0.05 mmol/L, which is at least on par with more complex analysis techniques. Additionally, several different reversed phase columns are assessed to reduce 2nd dimension (²D) time and, hence, overall analysis time while maintaining the possibility for quantification. A reduction in overall analysis time of about 30% as compared to the state-of-the-art is achieved by using a YMC Triart BIO C4 column as ²D.

Significance: Through the enhancements introduced in this study, GPC-HPLC-UV/VIS emerges as a unique technique for the analysis of lignin depolymerization product pools, which is capable of fast yet sufficiently in-depth analysis of a large volume of samples. This capability is indispensable for catalyst screening and fine-tuning reaction conditions.

Keywords: Lignin depolymerization; Lignin monomer quantification; Orbitrap high-resolution accurate-mass spectrometry; Two dimensional liquid chromatography.