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Chitosan chemical properties

The effectiveness of zeolites in catalysis and separation can often be improved by the textural and chemical properties of the matrices in which they are imbedded. Chitosan gels issued from renewable resources are already used as supports for the preparation of heterogeneous catalysts in the form of colloids, flakes or gel beads [1, 2], In this study we present several methods for the incorporation of zeolites in chitosan matrices and characterize the synergic effect of the components on the properties of the composite. [Pg.389]

Shell wastes from shrimp, crab, and lobster processing industries are the traditional source of chitin. However, commercial production of chitosan by deacetylation of crustacean chitin with a strong alkali appears to have limited potential for industrial acceptance because of seasonal and limited supply, difficulties in processing, particularly with the large amount of waste of concentrated alkaline solution causing environmental pollution, and inconsistent physico-chemical properties (Chatterjee et ah, 2005). [Pg.123]

Because the biological properties of chitosan are dependent on its physico-chemical properties such as molecular weight (MW) and degree of deacetylation (DD), uniform physico-chemical properties are a prerequisite to specific industrial applications. As an alternative method, fermentation technology for chitosan preparation from fungal cell walls has received much attention as an eco-friendly pathway. Rane and... [Pg.123]

Liu, J. N., Xia, W. S., and Zhang, J. L. (2008a). Effects of chitosans physico-chemical properties on binding capacities of lipid and bile salts in vitro. Chin. Food Sci. 29, 45 9. [Pg.134]

Chitosan has been the focus of reasearch as a pharmaceutical excipient due to its specific chemically and biologically favorable features [6-8]. As chitosan is soluble in acidic aqueous solutions, it can be processed under acidic conditions. By contrast, as the product made by chitosan is insoluble at neutral or basic pH, it behaves as a delivery system under such conditions. These chemical properties allow chitosan to control drug delivery. Further,... [Pg.57]

A. Structure, Physical, and Chemical Properties of Chitin and Chitosan... [Pg.93]

A. STRUCTURE, PHYSICAL, AND CHEMICAL PROPERTIES OF CHITIN AND CHITOSAN... [Pg.95]

Although chitosan-coated nanoparticles showed contradictory results in complement activation depending on the conformation of the chains at the nanoparticle surface [20], the level of complement activation induced by chitosan was also influenced by the physico-chemical properties of the polysaccharide, including its solubility, degree of deacetylation, and molecular weight [20, 96-98]. Using different... [Pg.132]

Suzuki Y, Okamoto Y, Morimoto M, et al. (2000). Influence of physico-chemical properties of chitin and chitosan on complement activation. Carbohyd. Polym. 42 307-310. [Pg.153]

In order to modify or enhance specific properties of chitosan, chemical derivatives have been synthesized by using the amines and hydroxyl groups in the molecular structure. Some examples include trimethyl chitosan, glycol chitosan, carboxymethyl chitosan, half-acetylated chitosan, and thiolated chitosan." ... [Pg.1244]

In this chapter, we first discuss the chemical and physical properties of chitosan, including the synthesis, modification, molecular structure, characterization, and structure-property relationship. Second, we review the topics of biocompatibility, biodegradability, and antimicrobial activity of chitosan. These properties make chitosan a potential biomaterial for many biomedical applications. [Pg.92]

Tolaimate, A., Desbrieres, J., Rhazi, M. and Alagui, A. (2003) Contribution to the preparation of chitins and chitosans with controlled physico-chemical properties. Polymer, 44(26), 7939-7952. [Pg.79]

The DD is the key property that affects the physical and chemical properties of chitosan, such as solubility, chemical reactivity and biodegradabdity and, consequently their applications. A quick test to differentiate between chitin and chitosan is based on solubdity and nitrogen content. Chitin is soluble in 5% lithium chloride/N,N-dimethylacetamide solvent [LiCI/DMAc] and insoluble in aqueous acetic add while the op>posite is true of chitosan. The nitrogen content in purified samples is less than 7% for chitin and more than 7% for chitosan (Dash et al, 2011 Rinaudo, 2006). [Pg.44]

The principle of functional group modification is to alter existing physical and chemical properties of chitosan in order to promote its capacity to deliver pDNA. Examples of vectors derived by functional group modification include thiolated chitosan (CSH) and A-acetylated chitosan. [Pg.70]

The poor solubility, low surface area, and porosity of chitin and chitosan are the major limiting factors in their utilization. Chitosan can be modified by physical or chemical processes in order to improve the mechanical and chemical properties. Chemical modification of chitosan has two main aims (a) to improve the metal adsorption properties and (b) to change the solubility properties of chitosan in water or acidic medium. The substitution chemical reactions involve the NH2 group in the C2 position or the OH groups in the C3 and Cg positions of acetylated and deacetylated units. Chitosan membrane is swollen in water the amino groups may be protonated and leave the hydroxide ions free in water, which may contribute to the ionic conduction in the membrane. [Pg.563]

Naggi, A.M., Torri, G., Compagnoni, T., and Casu, B. 1986. Synthesis and physico-chemical properties of a polyampholyte chitosan 6-sulfate. In MuzzarelU, R.A.A., Jeuniaux, C., and Gooday, G.W. (eds.), Chitin in Nature and Technology. Plenum Publishing Corporation, New York, pp. 371 07. [Pg.582]


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Chemical Properties of Chitosan

Chitosan properties

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