Cellulose acetate, SCA

Marques et al. (2002) studied the biocompatibility of starch-based polymers. The materials used for this study were (i) a 50/50 (wt%) blend of cornstarch and ethylene vinyl alcohol (SEVA-C), (ii) SEVA-C reinforced with 30 % (wt) of hydroxyapatite, (iii) a 50/50 (wt%) blend of cornstarch and cellulose acetate (SCA), and (iv) SCA reinforced with 30 % (wt) of hydroxyapatite. In the composites the average size of 90 % of the HA particles was found to be below 6.5 mm. Cytotoxicity tests with the extract of the materials were performed in order to evaluate the presence and or release of toxic leachables and degradation products. Cell material interactions on the surface of the polymers were observed by scanning electron microscopy (SEM) and related to the materials formulations. The short-term effect of leachables from starch-based polymers was quantified by exposing L929 cell to the degradation products released by those materials after immersion in culture medium. 

The biocompatibility of two different blends of corn-starch, SEVA and starch/cellulose acetate (SCA), and their respective composites with HAp, were studied by Marques et al. [274]. Researchers found that both types of starch-based polymers exhibit a cytocompatibility that might allow for their use as biomaterials Eurthermore SEVA blends were found to be less cytotoxic for the tested cell line, although cells adhere better to SCA surface. Considering the overall behaviour of SEVA, SCA and their composites with HAp, it can be expected that their cytocompatibility will allow for their use in the future in applications such as bone replacement/fixation and/or tissue engineering scaffolding. 

Different degradable porous architectures have thus been developed using polymers based on blends of com starch with poly(ethylene-co-vinyl alcohol)(SEVA-C, Novamont, Italy) and cellulose acetate (SCA, Novamont, ltaly)(Gomes et al., 2001). These materials present a non-cytotoxic behavior and are under consideration for a wide range of biomedical applications, such as scaffolds for bone-tissue engineering (Salgado et al., 2004). 

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