Alginate/chitosan films

Da Silva MA, lamanaka BT, Taniwaki MH, Kieckbusch TG. Evaluation of the antimicrobial potential of alginate and alginate/chitosan films containing potassium sorbate and natamycin. Packag Technol Sci 2013 26 (8) 479 92. 

Chitosan films exhibit low swelling in water, but membranes with diverse hydrophilic aptitudes can be prepared through the formation of mixtures or semi-interpenetrated and interpenetrated networks of chitosan with highly hydrophilic polymers like poly(vinyl alcohol), poly(vinylpyrrolidone) and gelatin [164]. PEC of chitosan with polyanions of natural origin like alginate, pectin or CMC or with synthetic ones, like poly(acrylic acid), have been investigated as matrices for controlled-release systems [165]. 

Sodium Alginate-Chitosan Composite Films for Fabrication of Antihacterial Silver Nanoparticles... 

This review highlights the uses of chitosan-based derivatives for various biomedical applications. Chitosan has offered itself as a versatile and promising biodegradable polymer. In addition, chitosan possesses immense potential as an antimicrobial packaging material owing to its antimicrobial activity and non-toxicity. The functional properties of chitosan films can be improved when chitosan films are combined with other film forming materials such as SF, alginate and other biopolymers. All these studies indicate that, in the near future, several commercial biomedical products based on silk fibroin and chitosan will be available in the world market. 

An alternative to grafted PNIPAAm surfaces, which requires previous activation of the supporting substrate, is offered by multilayer polymer assemblies, such as chitosan-grafted-PNIPAAm and alginate multilayered films (Martins et a/., 2011). The layer-by-layer approach allows mild conditions for fabrication and precise control over the thickness of the coatings, which is a relevant issue for modulating cellular adhesiveness. 

A new composite biosorbent has been prepared by coating chitosan onto acid treated oil palm shell eharcoal (AOPSC) and is used for the removal of chromium [142]. Bromine pretreated ehitosan was found to be promising adsorbent for lead (II) removal from water [157]. The ability of chitosan as an adsorbent for Cu (II) and Cr (VI) ions in aqueous solution was studied by Schmuhl et al. (2001). Polymer blend films of chitin and bentonite were prepared and this blended polymer was used as an adsorbent for the removal of copper and chromium from the dye effluent [169]. The alginate-chitosan hybrid gel beads were prepared and it is used to adsorb divalent metal ions [182]. 

The materials used in these type of films include lipids, polysaccharides, and proteins. Starch (Maizura and others 2007), methylcellulose (Olivas and others 2003), hydroxypropyl cellulose (Brindle and Krochta 2008), chitosan (No and others 2007), xanthan gum (Mei and others 2002), alginate or zein (Zapata and others 2008), and soy protein (Park and others 2001) have been used for edible coatings. 

Remunan-Lopez C, Bodmeier R (1997) Mechanical, water uptake and permeability properties of crosslinked chitosan glutamate and alginate films. J Control Rel 44 215-225... 

The properties of various film-forming polysaccharides, such as alginates, pectins, starches, dextrins, cellulose, carrageenan, gums, chitosans and their derivatives have been investigated for a long time and reviewed by Nisperos-Carriedo (1994). Then-wide uses in the food industry have been favoured by their abundance, variability and low-cost, and are summarized in Tables 23.2(a) and (b). 

Edible films and coatings are thin materials made from biological macromolecules (biopolymers).1 The main biopolymers used in preparing biofilms are polysaccharides2 and proteins.3,4 Among the most studied polysaccharides are pectin, cellulose and derivatives, alginates, carrageenan, chitosan and starch.1 5... 

Yan XL, Khor E, Lim LY. Chitosan-alginate films prepared with chitosans of different molecular weights. J Biomed Mater Res 2001 58 358-365. 

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