TY - JOUR
T1 - 2D Assignment and quantitative analysis of cellulose and oxidized celluloses using solution-state NMR spectroscopy
AU - Koso, Tetyana
AU - Rico del Cerro, Daniel
AU - Heikkinen, Sami
AU - Nypelö, Tiina
AU - Buffiere, Jean
AU - Perea-Buceta, Jesus E.
AU - Potthast, Antje
AU - Rosenau, Thomas
AU - Heikkinen, Harri
AU - Maaheimo, Hannu
AU - Isogai, Akira
AU - Kilpeläinen, Ilkka
AU - King, Alistair W.T.
PY - 2020/9/1
Y1 - 2020/9/1
N2 - The limited access to fast and facile general analytical methods for cellulosic and/or biocomposite materials currently stands as one of the main barriers for the progress of these disciplines. To that end, a diverse set of narrow analytical techniques are typically employed that often are time-consuming, costly, and/or not necessarily available on a daily basis for practitioners. Herein, we rigorously demonstrate a general quantitative NMR spectroscopic method for structural determination of crystalline cellulose samples. Our method relies on the use of a readily accessible ionic liquid electrolyte, tetrabutylphosphonium acetate ([P-4444][OAc]):DMSO-d(6), for the direct dissolution of biopolymeric samples. We utilize a series of model compounds and apply now classical (nitroxyl-radical and periodate) oxidation reactions to cellulose samples, to allow for accurate resonance assignment, using 2D NMR. Quantitative heteronuclear single quantum correlation (HSQC) was applied in the analysis of key samples to assess its applicability as a high-resolution technique for following cellulose surface modification. Quantitation using HSQC was possible, but only after applying T(2)correction to integral values. The comprehensive signal assignment of the diverse set of cellulosic species in this study constitutes a blueprint for the direct quantitative structural elucidation of crystalline lignocellulosic, in general, readily available solution-state NMR spectroscopy.[GRAPHICS].
AB - The limited access to fast and facile general analytical methods for cellulosic and/or biocomposite materials currently stands as one of the main barriers for the progress of these disciplines. To that end, a diverse set of narrow analytical techniques are typically employed that often are time-consuming, costly, and/or not necessarily available on a daily basis for practitioners. Herein, we rigorously demonstrate a general quantitative NMR spectroscopic method for structural determination of crystalline cellulose samples. Our method relies on the use of a readily accessible ionic liquid electrolyte, tetrabutylphosphonium acetate ([P-4444][OAc]):DMSO-d(6), for the direct dissolution of biopolymeric samples. We utilize a series of model compounds and apply now classical (nitroxyl-radical and periodate) oxidation reactions to cellulose samples, to allow for accurate resonance assignment, using 2D NMR. Quantitative heteronuclear single quantum correlation (HSQC) was applied in the analysis of key samples to assess its applicability as a high-resolution technique for following cellulose surface modification. Quantitation using HSQC was possible, but only after applying T(2)correction to integral values. The comprehensive signal assignment of the diverse set of cellulosic species in this study constitutes a blueprint for the direct quantitative structural elucidation of crystalline lignocellulosic, in general, readily available solution-state NMR spectroscopy.[GRAPHICS].
KW - Cellulose dissolution
KW - Ionic liquid
KW - Nitroxyl radical
KW - Periodate
KW - Quantitative HSQC
KW - TEMPO
UR - http://www.scopus.com/inward/record.url?scp=85088660039&partnerID=8YFLogxK
U2 - 10.1007/s10570-020-03317-0
DO - 10.1007/s10570-020-03317-0
M3 - Article
AN - SCOPUS:85088660039
VL - 27
SP - 7929
EP - 7953
JO - Cellulose
JF - Cellulose
SN - 0969-0239
IS - 14
ER -