title: Analysis of crystallinity changes in cellulose II polymers using carbohydrate-binding modules.
abstract: Carbohydrate-binding modules (CBMs) are a set of tools that can be used as molecular probes for studying plant cell walls and cellulose-based substrates. CBMs from enzymes of bacterial and fungal origin present a range of recognition capabilities for crystalline and amorphous cellulose. Here cellulose-directed CBMs have been used to visualize and quantify crystallinity changes in cellulose II-based polymers following NaOH treatment. Cellulose II polymers used were in the form of lyocell fibers, which are derived from eucalyptus wood pulp. The supramolecular structure, morphology, and existence of 'skin-core' model in the fiber were examined using CBM-labeling techniques. Changes in cellulose crystallinity showed maxima at 3.33 mol dm(-3) NaOH (under treatment conditions of 49 Nm(-1) at 25 °C) and 4.48 mol dm(-3) NaOH (under treatment conditions of 147 Nm(-1) at 40 °C); CBM methods were also suitable for quantifying changes within amorphous regions. Quantification of crystallinity changes using CBM labeling techniques was achieved in combination with image analysis, which was shown to reflect the same crystallinity changes as measured using ATR-FTIR methods. It was demonstrated that CBM-labeling techniques were able to validate the proposed 'skin-core' model of lyocell fibers, comprising a semi-permeable fiber skin and a porous core.
authors.affiliation: Sustainable Materials Research Group, Centre for Technical Textiles, University of Leeds, Leeds LS2 9JT, UK; Christian Doppler Laboratory for Textile and Fiber Chemistry in Cellulosics, Research Institute of Textile Chemistry and Textile Physics, University of Innsbruck, Höchsterstraße 73, A-6850 Dornbirn, Austria.
authors.forename: Ján
authors.initials: J
authors.lastname: Široký
authors.affiliation: Centre for Plant Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.
authors.forename: Thomas A S
authors.initials: TA
authors.lastname: Benians
authors.affiliation: Sustainable Materials Research Group, Centre for Technical Textiles, University of Leeds, Leeds LS2 9JT, UK.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Russell
authors.affiliation: Christian Doppler Laboratory for Textile and Fiber Chemistry in Cellulosics, Research Institute of Textile Chemistry and Textile Physics, University of Innsbruck, Höchsterstraße 73, A-6850 Dornbirn, Austria.
authors.forename: Thomas
authors.initials: T
authors.lastname: Bechtold
authors.affiliation: Centre for Plant Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.
authors.forename: J
authors.initials: J
authors.lastname: Paul Knox
authors.affiliation: Sustainable Materials Research Group, Centre for Technical Textiles, University of Leeds, Leeds LS2 9JT, UK.
authors.forename: Richard S
authors.initials: RS
authors.lastname: Blackburn
mesh_terms: D002482:Cellulose / Q000737:chemistry*; D003460:Crystallization; D012972:Sodium Hydroxide / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D012972:Sodium Hydroxide; D002482:Cellulose