Biocompatibility hyaluronic acid

Biodegradable polymers, both synthetic and natural, have gained more attention as carriers because of their biocompatibility and biodegradability and therewith the low impact on the environment. Examples of biodegradable polymers are synthetic polymers, such as polyesters, poly(orfho-esters), polyanhydrides and polyphosphazenes, and natural polymers, like polysaccharides such as chitosan, hyaluronic acid and alginates. 

Several other biodegradable, biocompatible, injectable polymers are being investigated for drug delivery systems. They include polyvinyl alcohol, block copolymer of PLA-PEG, polycyanoacrylate, polyanhydrides, cellulose, alginate, collagen, gelatin, albumin, starches, dextrans, hyaluronic acid and its derivatives, and hydroxyapatite. ... 

Hyaluronic acid is a linear polysaccharide formed from disaccharide units containing N-acetyl-D-glucosamine and glucuronic acid. Since it is present in almost all biological fluids and tissues, hyaluronic acid-based materials are very useful in biomedical applications. After cellulose, chitin is the second most abundant natural polysaccharide resource on earth. Chitin and its de-acetylated derivative chitosan are natural polymers composed of N-acetylglucosamine and glucosamine. Both chitin and chitosan have excellent properties such as biodegradability, biocompatibility, non-toxicity, hemostatic activity and antimicrobial activity. Chitin and its derivatives are widely used in various fields of medicine. 

Bulpitt P, Aeschlimann D (1999). New strategy for chemical modification of hyaluronic acid preparation of functionalized derivatives and their use in the formation of novel biocompatible hydrogels. J. Biomed. Mater. Res. 47 152-169. 

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. 

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