A Complementary Multitechnique Approach to Assess the Bias in Molecular Weight Determination of Lignin by Derivatization-Free Gel Permeation Chromatography
Papp, Daniel LU ; Carlström, Göran LU
; Nylander, Tommy
LU
; Sandahl, Margareta
LU
and Turner, Charlotta
LU
(2024)
In Analytical Chemistry
96(26).
p.10612-10619
- Abstract
The growing interest in lignin valorization in the past decades calls for analytical techniques for lignin characterization, ranging from wet chemistry techniques to highly sophisticated chromatographic and spectroscopic methods. One of the key parameters to consider is the molecular weight profile of lignin, which is routinely determined by size-exclusion chromatography; however, this is by no means straightforward and is prone to being hampered by considerable errors. Our study expands the fundamental understanding of the bias-inducing mechanisms in gel permeation chromatography (GPC), the magnitude of error originating from using polystyrene standards for mass calibration, and an evaluation of the effects of the solvent and type of... (More)
The growing interest in lignin valorization in the past decades calls for analytical techniques for lignin characterization, ranging from wet chemistry techniques to highly sophisticated chromatographic and spectroscopic methods. One of the key parameters to consider is the molecular weight profile of lignin, which is routinely determined by size-exclusion chromatography; however, this is by no means straightforward and is prone to being hampered by considerable errors. Our study expands the fundamental understanding of the bias-inducing mechanisms in gel permeation chromatography (GPC), the magnitude of error originating from using polystyrene standards for mass calibration, and an evaluation of the effects of the solvent and type of lignin on the observed bias. The developed partial least-squares (PLS) regression model for lignin-related monomers revealed that lignin is prone to association mainly via hydrogen bonding. This hypothesis was supported by functional group-based analysis of the bias as well as pulse field gradient (pfg) diffusion NMR spectroscopy of model compounds in THF-d8. Furthermore, although the lack of standards hindered drawing conclusions based on functionalities, direct infusion electrospray ionization mass spectrometry indicated that the relative bias decreases considerably for higher molecular weight species. The results from pfg-diffusion NMR spectroscopy on whole lignin samples were comparable when the same solvents were used in both experiments; in addition, the comparison between results obtained by pfg-diffusion NMR in different solvents gives some additional insights into the aggregation.
(Less)
- author
- Papp, Daniel
LU
; Carlström, Göran
LU
; Nylander, Tommy
LU
; Sandahl, Margareta
LU
and Turner, Charlotta
LU
- organization
- publishing date
- 2024-07-02
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Analytical Chemistry
- volume
- 96
- issue
- 26
- pages
- 8 pages
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- pmid:38888104
- scopus:85196526222
- ISSN
- 0003-2700
- DOI
- 10.1021/acs.analchem.4c01187
- language
- English
- LU publication?
- yes
- id
- 18cfa1eb-471e-4bdc-a85d-6ab74230df9e
- date added to LUP
- 2024-09-02 10:37:07
- date last changed
- 2024-09-03 03:00:03
@article{18cfa1eb-471e-4bdc-a85d-6ab74230df9e,
abstract = {{<p>The growing interest in lignin valorization in the past decades calls for analytical techniques for lignin characterization, ranging from wet chemistry techniques to highly sophisticated chromatographic and spectroscopic methods. One of the key parameters to consider is the molecular weight profile of lignin, which is routinely determined by size-exclusion chromatography; however, this is by no means straightforward and is prone to being hampered by considerable errors. Our study expands the fundamental understanding of the bias-inducing mechanisms in gel permeation chromatography (GPC), the magnitude of error originating from using polystyrene standards for mass calibration, and an evaluation of the effects of the solvent and type of lignin on the observed bias. The developed partial least-squares (PLS) regression model for lignin-related monomers revealed that lignin is prone to association mainly via hydrogen bonding. This hypothesis was supported by functional group-based analysis of the bias as well as pulse field gradient (pfg) diffusion NMR spectroscopy of model compounds in THF-d<sub>8</sub>. Furthermore, although the lack of standards hindered drawing conclusions based on functionalities, direct infusion electrospray ionization mass spectrometry indicated that the relative bias decreases considerably for higher molecular weight species. The results from pfg-diffusion NMR spectroscopy on whole lignin samples were comparable when the same solvents were used in both experiments; in addition, the comparison between results obtained by pfg-diffusion NMR in different solvents gives some additional insights into the aggregation.</p>}},
author = {{Papp, Daniel and Carlström, Göran and Nylander, Tommy and Sandahl, Margareta and Turner, Charlotta}},
issn = {{0003-2700}},
language = {{eng}},
month = {{07}},
number = {{26}},
pages = {{10612--10619}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Analytical Chemistry}},
title = {{A Complementary Multitechnique Approach to Assess the Bias in Molecular Weight Determination of Lignin by Derivatization-Free Gel Permeation Chromatography}},
url = {{http://dx.doi.org/10.1021/acs.analchem.4c01187}},
doi = {{10.1021/acs.analchem.4c01187}},
volume = {{96}},
year = {{2024}},
}