Chitosan preparation

Galactosylated chitosan prepared from lactobionic acid and chitosan with l-ethyl-3-(3-dimethylaminopropyl)-carbodiimideand N-hydroxysuccinimide was a good extracellular matrix for hepatocyte attachment [155] (Fig. 4). Furthermore, graft copolymers of galactosylated chitosan with poly(ethylene glycol) or poly(vinyl pyrrolidone) were useful for hepatocyte-targeting DNA carrier [156,157]. 

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... 

Zhou, K., Xia, W., Zhang, C, and Yu, L. (2006). In vitro binding of bile acids and triglycerides by selected chitosan preparations and their physicochemical properties. LWT Food Sci. Technol. 39,1087-1092. 

Since the concentrations of insulin to be administered in the sheep model would have been large, the insulin-loaded chitosan nanoparticles were not investigated in that model. However, the pharmacodynamics and pharmacokinetics of various insulin-chitosan preparations were compared with postloaded insulin-chitosan nanoparticles. It was found that chitosan solution and chitosan powder formulations were far better, with the chitosan powder formulation showing a bioavailability of 17% as against 1.3 and 3.6% for the chitosan nanoparticles and chitosan solution [72], The effects of the concentration and osmolarity of chitosan and the presence of absorption enhancers in the chitosan solution on the permeation of insulin across the rabbit nasal mucosa in vitro and in vivo were investigated, and the same... 

It therefore seems probable that, imless very drastic conditions are employed during chitosan preparation, the product will have an appreciable (20-30%) acetyl content. However, acetyl contents for chitosan can be decreased to neghgiblevaluesby fractionation or retreatment with alkali. ... 

Matrix composed of collagen and chitosan prepared by using crosslinking agent EDC in... 

Dai, T.H., Tanaka, M., Huang, Y.Y., Hamblin, M.R., 2011. Chitosan preparations for wounds and bums antimicrobial and wound-healing effects. Expert Review of Anti-Infective... 

Shinya, Y., Tsnrnshima, H., Tsnrnmi, T., Kajiuchi, T., Kam, and Leong, W. Polyelectrolyte complex films derived from polyethyleneoxide—maleic acid copolymer and chitosan Preparation and characterization. Macromol. Biosci. (2004) 526-531. 

Figure 14.6 SEM images of re-swollen films of BC [a], BC-chitosan prepared by adding 0.75% chitosan of MW 30,000 [b] and of MW 80,000 (c) in the culture medium.

No, H. K., Lee, S. H., Park, N. Y, and Meyers, S. P., Comparison of physicochemical, binding, and antibacterial properties of chitosans prepared without and with deproteinization process,... 

Shamji, M.F., Hwang, P., Bullock, R.W., Adams, S.B., Nettles, D.L. Setton, L.A. 2008, Release and activity of anti-TNFa therapeutics from injectable chitosan preparations for local drug delivery . Journal of Biomedical Materials Research Part B Applied Biomaterials, vol. 90, no. 1, pp. 319-326. 

Figure 25.2 Schematic representation of the different steps involved in chitin/chitosan preparation procedures. In this diagram a second treatment with dilute NaOH is considered for chitin isolation in order to remove any residual protein.

Chitin isolation processes are generally performed through the following consecutive steps raw material conditioning, protein extraction (deproteinization), removal of inorganic components (demineralization) and decolouration. This sequence is preferred if the isolated protein is to be used as food additive for livestock feeding. Otherwise, demineralization can be carried out first [10]. A brief account of these processes will be given below. A more detailed description of chitin isolation (and chitosan preparation) can be found elsewhere [5, 8, 11]. 

Sashiwa, H., Thompson, J. M., Das, S. K., Shigemasa, Y., Tripathy, S., and Roy, R. 2000. Chemical modification of chitosan Preparation and lectin binding properties of a-galactosyl-chitosan conjugates. Potential inhibitors in acute rejection following xenotransplantation. Biomacromolecides 1 303—305. 

Li, J., Y. M. Du, and H. B. Liang. 2006a. Low molecular weight water-soluhle chitosans Preparation with the aid of cellulase, characterization, and solubihty. J. Appl. Polym. Sci. 102 1098-1105. 

Prashanth, K. V. H., F. S. Kittur, and R. N. Tharanathan. 2002. Solid state structure of chitosan prepared under different V-deacetylating conditions. Carbohydr. Polym. 50 27-33. 

Lin, S.-B., Lin, Y.-C., and Chen, H.-H. 2009. Low molecular weight chitosan prepared with the aid of cellulose, lysozyme and chitinase Characterization and antibacterial activity. Food Chem. 116 47-53. 

Kittur F. S., Vishu Kumar A. B., and Tharanathan R. N. 2003. Low molecular weight chitosans—Preparation by depolymerization with Aspergillus niger pectinase, and characterization. Carbohydr Res 338 1283-1290. 

FIGURE 31.21 Effect of pH on humic acid adsorption onto cross-linked CM-chitosan (prepared from 40% aqueous solution at 100kGy). Humic acid concentration 50ppm, adsorption time 24h. (From Zhao, L. et al., Nucl. Sci. Tech., 18, 42, 2007. With permission.)... 

Vishu Kumar, A. B., Varadaraj, M. C., Gowda, L. R., and Tharanathan, R. N. 2007. Low molecular weight chitosans-preparation with the aid of pronase, characterization and their bactericidal activity towards Bacillus cereus and Escherichia coli. Biochem. Biophys. Acta 1770 495-505. 

Tseng, R.-L., Wn, F.-C., and Jnang, R.-S. 1999. Pore structure and metal adsorption ability of chitosan prepared from fishery wastes. J. Environ. Sci. Health A 34(9) 1815—1828. 

Wu, F., Tseng, T., and Juang, R. 2000. Comparative adsorption of metal and dye on flake and bead-types of chitosan prepared from fishery wastes. J. Hazard. Mater. B73 63-75. 

Younes, I., Rinaudo, M., 2015. Chitin and chitosan preparation from marine sources, structure, properties and apphcations. Marine Drugs 13, 1133—1174. 

Determinations of metals in chitosan prepared from crab shells with... 

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