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Budischowsky D, Sulaeva I, Støpamo FG, Lehrhofer AF, Hettegger H, Várnai A, Eijsink VGH, Rosenau T, Potthast A. Oxidized reducing ends in celluloses: Quantitative profiling relative to molar mass distribution by fluorescence labeling. Carbohydr Polym 2024; 340:122210. [PMID: 38858031 DOI: 10.1016/j.carbpol.2024.122210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 06/12/2024]
Abstract
Fluorescence labeling with N-(1-naphthyl)ethylenediamine is highly effective for quantifying oxidized reducing end groups (REGs) in cellulosic materials. When combined with size exclusion chromatography in DMAc/LiCl, along with fluorescence / multiple-angle laser light scattering / refractive index detection, a detailed profile of C1-oxidized REGs relative to the molecular weight distribution of the cellulosic material can be obtained. In this work, the derivatization process was extensively optimized, to be carried out heterogeneously in the solvent N-methyl-2-pyrrolidone. Furthermore, we show that to achieve high selectivity for carboxyl groups at the C1 position, keto and aldehyde groups need to be selectively reduced (e.g., by NaBH4), and carboxyl groups other than at C1 need to be blocked (e.g., by methylation with (trimethylsilyl)diazomethane) prior to fluorescence labeling of carboxyl groups at C1 position. Finally, we demonstrate the practical value of the analytical method by measuring the content of the C1-oxidized REGs in cellulose samples after chemical (by Pinnick oxidation) or enzymatic (by treatment with C1-oxidizing LPMO enzymes) oxidation of various pulp samples.
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Affiliation(s)
- David Budischowsky
- Institute of Chemistry of Renewable Resources, Department of Chemistry, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, A-1190 Vienna, Austria.
| | - Irina Sulaeva
- Institute of Chemistry of Renewable Resources, Department of Chemistry, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, A-1190 Vienna, Austria; Core Facility Analysis of Lignocellulosics (ALICE), University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Strasse 24, A-3430 Tulln, Austria.
| | - Fredrik G Støpamo
- Faculty of Chemistry, Biotechnology and Food Science, NMBU - Norwegian University of Life Sciences, 1432 Ås, Norway.
| | - Anna F Lehrhofer
- Institute of Chemistry of Renewable Resources, Department of Chemistry, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, A-1190 Vienna, Austria.
| | - Hubert Hettegger
- Institute of Chemistry of Renewable Resources, Department of Chemistry, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, A-1190 Vienna, Austria; Christian Doppler Laboratory for Cellulose High-Tech Materials, University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Strasse 24, A-3430 Tulln, Austria.
| | - Anikó Várnai
- Faculty of Chemistry, Biotechnology and Food Science, NMBU - Norwegian University of Life Sciences, 1432 Ås, Norway.
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, NMBU - Norwegian University of Life Sciences, 1432 Ås, Norway.
| | - Thomas Rosenau
- Institute of Chemistry of Renewable Resources, Department of Chemistry, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, A-1190 Vienna, Austria.
| | - Antje Potthast
- Institute of Chemistry of Renewable Resources, Department of Chemistry, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, A-1190 Vienna, Austria.
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Jursic BS, Zdravkovski Z. AB initio study of Diels-Alder reactions of 1,3,4-oxadiazole with ethylene, acrylonitrile, maleonitrile, fumaronitrile and 1,1-dicyanoethylene. Inverse order and ratio ofendo/exo reactivity. J PHYS ORG CHEM 1994. [DOI: 10.1002/poc.610071108] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Jursic BS, Zdravkovski Z. Semiempirical and ab initio transition state calculations for the transformation of N-acetyltetrazoles into corresponding 1,3,4-oxadiazoles. ACTA ACUST UNITED AC 1994. [DOI: 10.1016/0166-1280(94)80076-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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