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Updated: Jan 13, 2026
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Quantitative 31P NMR Analysis of Lignins and Tannins
Published on: August 2, 2021
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Advancing Quantitative 31P NMR Spectroscopy for Reliable Thiol Group Analysis.
Keven Walter1, Dominik P Hoch1, Enrico C Heyl1
1Humboldt-Universität zu Berlin, Department of Chemistry, Laboratory for Organic Synthesis of Functional Systems, Brook-Taylor-Str. 2, 12489 Berlin, Germany.
ACS Macro Letters
|January 7, 2026
Summary
A new 31P NMR method using TMDP reagent accurately quantifies thiols in polymers and materials. This technique offers superior selectivity over traditional assays, even for complex or degraded thiol samples.
Area of Science:
- Polymer Chemistry
- Materials Science
- Analytical Chemistry
Background:
- Accurate thiol quantification is crucial for thiol-X-ligation in polymer and materials synthesis.
- Conventional methods like Ellman's test have limitations with hydrophobic or multifunctional thiols.
Purpose of the Study:
- To develop a broadly applicable and accurate method for thiol quantification.
- To extend 31P NMR spectroscopy for thiol analysis.
Main Methods:
- Utilized 2-chloro-4,4,5,5-tetramethyl-1,3,2-dioxaphospholane (TMDP) as a phosphitylation reagent.
- Applied 31P NMR spectroscopy for thiol quantification.
- Validated the method against Ellman's assay and 1H NMR spectroscopy.
Main Results:
- The TMDP-based 31P NMR method provides high specificity and stable readout for thiol quantification.
- The method is applicable to a wide range of substrates, including polymeric multi thiols up to 8000 g·mol-1.
- Demonstrated superior selectivity and resolution compared to conventional assays, especially for technical-grade thiols.
Conclusions:
- The TMDP-enabled 31P NMR is a reliable tool for thiol quantification in diverse chemical contexts.
- This method offers simultaneous insights into hydroxy and carboxyl functionality.
- Establishes a new standard for thiol analysis in materials science and polymer chemistry.
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