Main properties and current applications of some polysaccharides as biomaterials

Abstract

This review concerns the applications of some polysaccharides in the domain of biomaterials and bioactive polymers. Natural polysaccharides from different sources have been studied for a long time, and their main properties are summarized in this paper; some of their derivatives obtained by chemical modification are also described. The main polysaccharides currently used in the biomedical and pharmaceutical domains are chitin and its derivative chitosan, hyaluronan and alginates. Alginates are well known for their property of forming a physical gel in the presence of divalent counterions (Ca, Ba, Sr) whereas carrageenans form a thermoreversible gel; these seaweed polysaccharides are mainly used to encapsulate different materials (cells, bacteria, fungi). Other promising systems are the electrostatic complexes formed when an anionic polysaccharide is mixed with a cationic polysaccharide (e.g. alginate/chitosan or hyaluronan/chitosan). An important development of the applications of polysaccharides can be predicted for the next few years in relation to their intrinsic properties such as biocompatibility and biodegradability in the human body for some of them; they are also renewable and have interesting physical properties (film‐forming, gelling and thickening properties). In addition, they are easily processed in different forms such as beads, films, capsules and fibres. Copyright © 2007 Society of Chemical Industry

Pullulan-based nanoparticles as carriers for transmucosal protein delivery

“…Carrageenan is one of the examples, having a limited number of reported applications in drug delivery. It is extracted from red seaweed and is composed of galactose and 3,6-anhydrogalactose units, linked by alternating α-(1,3) and β-(1,4) glycosidic bonds (Malafaya et al, 2007;Rinaudo, 2008). Our group has previously reported its use as nanoparticle forming material for drug delivery applications (Grenha et al, 2010b;Rodrigues et al, 2012b).…”

Preparation and physical properties of hyaluronic acid‐based cryogels

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