Polymer biocompatibility enhancement

The investigation of macromolecules has just begun to unfold its potential in our lives. Polymer modification is a major frontier introducing needed subtle or gross changes that allow biocompatability, enhanced thermal stability, increased solvent stability, etc. to the modified polymer. 

Enhancement of Polymer Biocompatibility. Films from about 0.5 g. of polymer were cast as for the water pickup determinations. The dry films were placed in 100 ml. of deionized water and left at ambient temperature. The water was changed every 24 hours for a total of 72 hours. The films were dried in vacuo at 50°C. Then the... 

Enhancement of Polymer Biocompatibility. The polymers as initially prepared were all found to be cytotoxic, most likely due to residual catalyst in the polymer. The extraction scheme was desiped to remove water and organic extractable materials. After following the extraction scheme, all of the polymers passed the cytotoxicity screen. 

Polymer grafting can be used to alter chemical and physical properties of a homopolymer. For example, Sawhney and Hubbell [18] grafted polyethyleneoxide to poly L-lysine to enhance biocompatibility of polylysine and improve the polylysine-alginate capsules. Stevenson and Sefton [19] modified alginate by grafting it with hydroxyalkyl methacrylate, again to improve the biocompatibility and to allow for polymerization by means of y-irradiation. Covalently modified (co)-polymers have not been evaluated in this study. 

The addition of biocompatible PEG or MPEG chains further enhances residence time of the compounds in the circulation. These hydrophilic polymers also provide some protection from interactions with blood cells and plasma proteins while, at the same time, increasing the molecular weight. 

Besides synthetic polymers and small molecules, biological or bioactive species are used in the functionalization of carbon nanotubes not only for water solubility but also enhanced biocompatibilities and biorecognition capabilities. Various proteins, DNAs, and carbohydrates have been covalently or noncovalently functionalized with carbon nanotubes, producing highly aqueous stable and biocompatible... 

Chitosan, a biocompatible and biodegradable polycationic polymer with low toxicity, is known for its swelling ability and permeation-enhancing properties and represents a polymer of choice for the preparation of microspheres intended for nasal administration [74],... 

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