Tissue engineering systems polymers

The functions of tissue-engineered systems also need to be properly evaluated. For example, thorough biomechanical testing of polymer constructs developed for tissue engineering will be required in addition to the biological and physicochemical properties so often studied. It is not sufficient to show that a construct excels in promoting cellular attachment, proliferation, and differentiation of the desired phenotypes and has a desirable degradation profile if it cannot meet the mechanical requirements of the intended application. 

Natural or synthetic HA has been intensively nsed in pure ceramic scaffolds as well as in polymer-ceramic composite systems. In fact, dne to calcinm phosphate osteocon-ductive properties, HA, TCP and BCP can be nsed as a scaffold matrix for bone-tissue engineering. However, these ceramic phases do not possess osteoinductive ability and their biodegradability is relatively slow, particularly in the case of crystalline HA (see Section 15.4.1). To overcome these drawbacks, biodegradable polymers added with osteogenic potential cells are used to make new biocomposite materials. Some of the tissue-engineered CP-polymer nanocomposite scaffolds are briefly described in the following sections, showing that both natural and synthetic polymers can be used to this aim. 

Skeletal Biocompatibility. Two Substituent Groups Attached to the Same Phosphazene Skeleton. Hydrolytical Instability 0 II — NH- CH2— C- OC2H5 Glycine or Lower Alkyl Aminoacid Esters Hydrolytically Unstable Polymers. Bioerodible Materials. Drug Delivery Systems. Tissue Engineering... 

Robert Langer, Polymer Systems for Controlled Release of Macromolecules, Immobilized Enzyme Medical Bioreactors, and Tissue Engineering J. J. Linderman, P. A. Mahama, K. E. Forsten, and D, A. Lauffenburger, Diffusion and Probability in Receptor Binding and Signaling Rakesh K. Jain, Transport Phenomena in Tumors... 

Recently, biodegradable polymers have been used to fabricate macro- and nanometer scale self-assembled systems such as microspheres (MSs), nanospheres (NSs), polymer micelles, nanogels, and polymersomes (Fig. 1). These have attracted growing interest because of their potential utility for drug delivery systems (DDS), tissue engineering, and other applications. To construct these self-assembled systems... 

Brown RQ, Mount A, Burg KJ (2005) Evaluation of polymer scaffolds to be used in a composite injectable system for intervertebral disc tissue engineering. J Biomed Mater Res A 74(l) 32-39... 

The polymer/SWCNT composites can be used as Scaffolds in tissue engineering. The donor-acceptor interactions can be used to assemble thin polymer/SWCNT films stepwise. This method also can be expended to more thermally and oxidatively stable polymer systems. For example, the P4VP/SWCNT films can be used as scaffolds for the synthesis of novel hybrid structures (Correa-Duaite et al., 2004). The polyethyl-enimine (PEI)-SWCNTs composites were used as a substrate for cultured neurons, and promoted neurite outgrowth and branching (Rouse et al., 2004). Correa-Duarte et al. (2004 Landi et al., 2005) reported that 3D-MWCNT-based networks are ideal candidates for scaffolds/matrices in tissue engineering. 

Langer, R. 1994. Polymer systems for controlled release of macromolecules, immobilized enzyme medical bioreactors, and tissue engineering. In Advances in Chemical Engineering, vol. 19. San Diego, CA Academic Press 1-50. 

Robert Langer, Polymer Systems for Controlled Release of Macromolecules, Immobilized Enzyme Medical Bioreactors, and Tissue Engineering... 

Silva et al. (2006) studied starch-based microparticles as a novel strategy for tissue engineering applications. They developed starch-based microparticles, and evaluated them for bioactivity, cytotoxicity, ability to serve as substrates for cell adhesion, as well as their potential to be used as delivery systems either for anti-inflammatory agents or growth factors. Two starch-based materials were used for the development of starch-based particulate systems (1) a blend of starch and polylactic acid (SPLA) (50 50 w/w) and (2) a chemically modifled potato starch, Paselli II (Pa). Both materials enabled the synthesis of particulate systems, both polymer and composite (with BG 45S5). A simple solvent extraction method was employed for the synthesis of SPLA and SPLA/BG microparticles, while for Pa and Pa/BG... 

Nerem R.M., Braddon L.G., Scliktar D., Ziegler T., Tissue engineering and the vascular system in Attala A., Mooney D.J., Vacanti J.P., Langer R. (eds) Synthetic Biodegradable Polymer Scaffolds, Birkhauser, Boston, 1997, 165— 185. 

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