Polysaccharides mucoadhesion

Ghelardi, E., et al. 2000. Effect of a novel mucoadhesive polysaccharide obtained from tamarind seeds on the intraocular penetration of gentamycin and ofloxacin in rabbits. J Antimicrob Che-mother 46 831. 

Chitosan An amino polysaccharide made by deacetylation of chitin. Its mucoadhesive properties make it ideal for oral and nasal administration (71-73)... 

The possibility of grafting synthetic polymer to chitosan has attracted much attention in the last years as a new way to modify the polysaccharide and develop practically useful derivatives. Graft copolymerization reactions introduce side chains and lead to the formation of novel types of tailored hybrid materials composed of natural and synthetic polymers. Grafting chitosan is a common way to improve chitosan properties such as formation of inclusion complexes [99], bacteriostatic effect [100], or to enhance adsorption properties [101, 102]. Although the grafting of chitosan modifies its properties, it is possible to retain some interesting characteristics such as mucoadhesivity [103], biocompatibility [104,105] and biodegradability [106]. 

Besides chitosan, numerous polysaccharides were evaluated as mucoadhesive ophthalmic vehicles polygalacturonic acid, xyloglucan, xanthan gum, gellan gum, pullulan, guar gum, scleroglu-can, and carrageenan. 

Many PECs are prepared using chitosan as the polycationic component, therefore they will be discussed separately. Chitosan, the product of N-deacetylation of chitin, is one of the most commonly used cationic polymers of pharmaceutical interest due to its biocompatibility, nontoxicity, and mucoadhesivity. It is frequently used to form PECs, often in combination with alginate, carrageenan," hyaluronic acid, chondroitin sulfate (CS)," carboxymethyl cellulose (CMC), or poly(galacturonic acid), since these are natural anionic polysaccharides with favorable pharmaceutical properties. 

Natural polysaccharides such as chitosan and alginate are promising materials for their applications, particularly in drug delivery, due to their favorable biocompatibility, biodegradability, pH sensitivity, and mucoadhesive properties [157, 158]. Covalently crossUnked polysaccharide-based nanospheres are quite stable compared with other several other t5q)es of polysaccharide-based nanospheres. The conventional methods for preparation of covalently crosslinked polysaccharide-based nanospheres include emulsion crosslinking, solvent evaporation, spray... 

Chitosan, a naturally occurring polysaccharide, is biocompatible, bioresorbable, biodegradable, and has mucoadhesive properties (Ilium, 1998). The polysaccharide hydroxyl and theamine groups can be easily functionalised under mUd reaction conditions to prepare modified chitosan derivatives with altered, desirable properties. 

Because chitosan is one of the few naturally occurring cationic polysaccharides, and because of its biocompatibility with the human body, it has been employed extensively in the development of anionic/cationic polysaccharide matrices for drug delivery (107). Such matrices include, for example, combinations of chitosan with xanthan or alginate, which form strong polyelectrolyte ionic gels capable of trapping active materials. Additionally, the strongly cationic polysaccharide has been shown to be mucoadhesive (108). 

Abstract Polysaccharides based nanomaterials have diverse applications in biomedical research. This chapter covers one of the major achievements in modification of polysaccharides using microwave irradiation and cationization methods. Additionally chapter focused on mucoadhesive polysaccharides and its recent advancement in nano drug delivery system. Applications such as gene transfection, bone regeneration and vaccine delivery are also separately discussed. 

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