Ultrastructure of iodine treated wood
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L. Donaldson
Abstract
Iodine staining has been used to study the orientation of cellulose microfibrils in wood using light microscopy. The aim of this work was to understand the exact nature of the staining reaction with iodine and to provide insight into the properties and organisation of the wood cell wall. Based on transmission electron microscopy it is apparent that precipitation of the iodine following treatment with nitric acid results in the formation of crystal cavities within the cell wall, which follow the orientation of the cellulose microfibrils. There is no evidence that iodine precipitates within “drying checks” as previously speculated. High resolution confocal reflectance microscopy of crystal cavity orientation indicates that the microfibril arrangement within pit borders can be both spiral and circular. Crystal cavities are much more abundant within the S1 layer than elsewhere. All of the cells examined had crystal cavities in the S1 region, which may be related to the reduced lignification at the S1/S2 boundary resulting in greater porosity of the cell wall at this location. Within the S2 region, clusters of crystal cavities are randomly distributed and occur in widely varying numbers among adjacent cell walls, suggesting variations in the porosity of the S2 wall within and among adjacent tracheids. Cavities form preferentially within more electron lucent regions of the cell wall. The random nature of crystal cavity formation within S2 clusters probably reflects the underlying random nature of the cell wall nanostructure. We conclude that iodine staining can provide important clues to the nanostructural properties of tracheid cell walls.
Copyright © 2004 by Walter de Gruyter GmbH & Co. KG
Articles in the same Issue
- The Bremen Cog of 1380 – An electron microscopic study of its degraded wood before and after stabilization with PEG
- Ultrastructure of iodine treated wood
- Effects of refining on the fibre structure of kraft pulps as revealed by FE-SEM and TEM: Influence of alkaline degradation
- Changes in the fiber wall during refining of bleached pine kraft pulp
- An unusual formation of tension wood in a natural forest Acacia sp.
- Changes in the surface properties of wood due to sanding
- Use of near infrared spectroscopy to predict the mechanical properties of six softwoods
- The creep of wood destabilized by change in moisture content. Part 1: The creep behaviors of wood during and immediately after drying
- Modeling the process of desorption of water in oak (Quercus robur L.) wood
- Moisture adsorption thermodynamics of wood from fractal-geometry approach
- Application of ionic liquids for electrostatic control in wood
- Ionic liquids in wood preservation
- New bis-quaternary ammonium and bis-imidazolium chloride wood preservatives
- Environmentally-benign wood preservatives based on an organic biocide:antioxidant combination: Ground-contact efficacy ratings and BHT depletion after four years of exposure
- Production of 2,5-dimethoxyhydroquinone by the brown-rot fungus Serpula lacrymans to drive extracellular Fenton reaction
- Fungal decay resistance of wood reacted with phosphorus pentoxide-amine system
- The use of organo alkoxysilane coupling agents for wood preservation
- Phenolic extractives from wood of birch (Betula pendula)
- Stability of arylglycerols during alkaline cooking
Articles in the same Issue
- The Bremen Cog of 1380 – An electron microscopic study of its degraded wood before and after stabilization with PEG
- Ultrastructure of iodine treated wood
- Effects of refining on the fibre structure of kraft pulps as revealed by FE-SEM and TEM: Influence of alkaline degradation
- Changes in the fiber wall during refining of bleached pine kraft pulp
- An unusual formation of tension wood in a natural forest Acacia sp.
- Changes in the surface properties of wood due to sanding
- Use of near infrared spectroscopy to predict the mechanical properties of six softwoods
- The creep of wood destabilized by change in moisture content. Part 1: The creep behaviors of wood during and immediately after drying
- Modeling the process of desorption of water in oak (Quercus robur L.) wood
- Moisture adsorption thermodynamics of wood from fractal-geometry approach
- Application of ionic liquids for electrostatic control in wood
- Ionic liquids in wood preservation
- New bis-quaternary ammonium and bis-imidazolium chloride wood preservatives
- Environmentally-benign wood preservatives based on an organic biocide:antioxidant combination: Ground-contact efficacy ratings and BHT depletion after four years of exposure
- Production of 2,5-dimethoxyhydroquinone by the brown-rot fungus Serpula lacrymans to drive extracellular Fenton reaction
- Fungal decay resistance of wood reacted with phosphorus pentoxide-amine system
- The use of organo alkoxysilane coupling agents for wood preservation
- Phenolic extractives from wood of birch (Betula pendula)
- Stability of arylglycerols during alkaline cooking
