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Monovalent Salt and pH-Induced Gelation of Oxidised Cellulose Nanofibrils and Starch Networks: Combining Rheology and Small-Angle X-ray Scattering

ABSTRACT: Water quality parameters such as salt content and various pH environments can alter the stability of gels as well as their rheological properties. Here, we investigated the effect of various concentrations of NaCl and different pH environments on the rheological properties of TEMPO-oxidised cellulose nanofibril (OCNF) and starch-based hydrogels. Addition of NaCl caused an increased stiffness of the OCNF:starch (1:1 wt%) blend gels, where salt played an important role in reducing the repulsive OCNF fibrillar interactions. The rheological properties of these hydrogels were unchanged at pH 5.0 to 9.0. However, at lower pH (4.0), the stiffness and viscosity of the OCNF and OCNF:starch gels appeared to increase due to proton-induced fibrillar interactions. In contrast, at higher pH (11.5), syneresis was observed due to the formation of denser and aggregated gel networks. Interactions as well as aggregation behaviour of these hydrogels were explored via ζ-potential measurements. Furthermore, the nanostructure of the OCNF gels was probed using small-angle X-ray scattering (SAXS), where the SAXS patterns showed an increase of slope in the low-q region with increasing salt concentration arising from aggregation due to the screening of the surface charge of the fibrils.

SUBMITTER: Hossain K

PROVIDER: S-EPMC8003611 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Production and Mechanical Characterisation of TEMPO-Oxidised Cellulose Nanofibrils/?-Cyclodextrin Films and Cryogels.

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| S-EPMC7288142 | biostudies-literature

Zwitterionic Acetylated Cellulose Nanofibrils.

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| S-EPMC6749602 | biostudies-literature

Influence of a Non-Ionic Surfactant in the Microstructure and Rheology of a Pickering Emulsion Stabilized by Cellulose Nanofibrils.

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| S-EPMC8587742 | biostudies-literature

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| S-EPMC6680576 | biostudies-literature

Gene expression profiles in human bronchial epithelial cells exposure to cellulose nanofibrils and microcrystalline cellulose

Project description:To evaluate the biological impact of cellulose nanofibrils (CNFs) at the transcriptional level, we conducted whole-genome microarray analyses on human bronchial epithelial cells (BEAS-2B) exposed to CNFs with different physicochemical properties. The results were compared with those from exposures to microcrystalline cellulose (MCC).

2024-11-20 | GSE282018 | GEO

Gene expression profiles in rat alveolar macrophages exposure to cellulose nanofibrils, microcrystalline cellulose, and lipopolysaccharide.

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2024-03-31 | GSE241791 | GEO

Lytic polysaccharide monooxygenases (LPMOs) facilitate cellulose nanofibrils production.

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| S-EPMC6589874 | biostudies-literature

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| S-EPMC6641346 | biostudies-literature

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| S-EPMC7559039 | biostudies-literature

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