TY - JOUR
T1 - Deuterated Bacterial Cellulose Dissolution in Ionic Liquids
AU - Raghuwanshi, Vikram Singh
AU - Cohen, Yachin
AU - Garnier, Guillaume
AU - Garvey, Christopher J.
AU - Garnier, Gil
PY - 2021/7/27
Y1 - 2021/7/27
N2 - Understanding the dissolution mechanism of deuterated bacterial cellulose (DBC) is important to engineer advanced material applications such as in quantifying and visualizing biomolecules at the cellulose interface for diagnostics. Small-angle neutron scattering (SANS) is applied to evaluate the distribution and volume fraction of dissolved DBC chains in 1-ethyl-3-methylimidazolium acetate (EMIM-Ac) ionic liquid (IL-h) solvent in three different ways: (i) DBC in IL-h, (ii) DBC in a mixture of N,N-dimethylformamide (DMF) with IL-h (IL-h/DMF), and (iii) modified DBC by dissolution in IL-h with dichloromethane (DCM), (DCM-DBC). EMIM-Ac is a highly viscous solvent, and the incorporation of DMF reduces its viscosity. DCM incorporation into EMIM-Ac leads to partial acetylation of the cellulose chains. The DBC dissolves differently in all the modified solvents studied. The DBC and DCM-DBC dissolution in IL-h shows the presence of surface fractals (power law relation of intensity to a scattering vector, q, of q-3.4) indicating compact aggregated DBC structures. The DBC structure is more open in the DMF/IL-h solvent, which is reflected in the SANS curve mass fractal analysis with a power law of q-2.5. At intermediate values of the scattering vector, a q-1 power law is observed, indicative of rigid segments of dissolved DBC chains. Analysis of the intensity in this range provides insights as to the dissolution mechanism. The observed higher intensity measured in the solutions of DBC and DCM-DBC in IL-h can be attributed to the tight binding adsorption of the acetate ions on the DBC surface. Moreover, the unique aspect of this experiment, using deuterated cellulose in a mixture of deuterated DMF with protiated EMINM-Ac, provides direct proof for formation of a shell layer of IL-h surrounding the DBC surface. The results obtained shed light on the dissolution mechanism of cellulose in EMIM-Ac, highlighting its potential application in engineering biosensors and bio-diagnostics.
AB - Understanding the dissolution mechanism of deuterated bacterial cellulose (DBC) is important to engineer advanced material applications such as in quantifying and visualizing biomolecules at the cellulose interface for diagnostics. Small-angle neutron scattering (SANS) is applied to evaluate the distribution and volume fraction of dissolved DBC chains in 1-ethyl-3-methylimidazolium acetate (EMIM-Ac) ionic liquid (IL-h) solvent in three different ways: (i) DBC in IL-h, (ii) DBC in a mixture of N,N-dimethylformamide (DMF) with IL-h (IL-h/DMF), and (iii) modified DBC by dissolution in IL-h with dichloromethane (DCM), (DCM-DBC). EMIM-Ac is a highly viscous solvent, and the incorporation of DMF reduces its viscosity. DCM incorporation into EMIM-Ac leads to partial acetylation of the cellulose chains. The DBC dissolves differently in all the modified solvents studied. The DBC and DCM-DBC dissolution in IL-h shows the presence of surface fractals (power law relation of intensity to a scattering vector, q, of q-3.4) indicating compact aggregated DBC structures. The DBC structure is more open in the DMF/IL-h solvent, which is reflected in the SANS curve mass fractal analysis with a power law of q-2.5. At intermediate values of the scattering vector, a q-1 power law is observed, indicative of rigid segments of dissolved DBC chains. Analysis of the intensity in this range provides insights as to the dissolution mechanism. The observed higher intensity measured in the solutions of DBC and DCM-DBC in IL-h can be attributed to the tight binding adsorption of the acetate ions on the DBC surface. Moreover, the unique aspect of this experiment, using deuterated cellulose in a mixture of deuterated DMF with protiated EMINM-Ac, provides direct proof for formation of a shell layer of IL-h surrounding the DBC surface. The results obtained shed light on the dissolution mechanism of cellulose in EMIM-Ac, highlighting its potential application in engineering biosensors and bio-diagnostics.
UR - http://www.scopus.com/inward/record.url?scp=85110936081&partnerID=8YFLogxK
U2 - 10.1021/acs.macromol.1c00833
DO - 10.1021/acs.macromol.1c00833
M3 - Article
AN - SCOPUS:85110936081
SN - 0024-9297
VL - 54
SP - 6982
EP - 6989
JO - Macromolecules
JF - Macromolecules
IS - 14
ER -