Poly biodegradable biomaterials

Lactic acid and levulinic acid are two key intermediates prepared from carbohydrates [7]. Lipinsky [7] compared the properties of the lactide copolymers [130] obtained from lactic acid with those of polystyrene and polyvinyl chloride (see Scheme 4 and Table 5) and showed that the lactide polymer can effectively replace the synthetics if the cost of production of lactic acid is made viable. Poly(lactic acid) and poly(l-lactide) have been shown to be good candidates for biodegradeable biomaterials. Tsuji [131] and Kaspercejk [132] have recently reported studies concerning their microstructure and morphology. 

Wang S, Andrew CA, et al. A new nerve guide conduit material composed of a biodegradable poly (phosphoester). Biomaterials, 2001, 22, 1157-1169. 

Presently enzymes can hardly be used to degrade artificial synthetic polymers unless it is under special conditions. It is worth noting that compounds like poly(vinyl alcohol), PVA, bacterial polymers and poly(e-caprolatone), PCL, that are biodegradable under outdoor conditions are degraded abiotically and thus very slowly in an animal body where they are not biodegradable. Despite this difficulty the number of artificial polymers proposed as biodegradable biomaterial candidates to replace biopolymers or biostable polymers is increasing. 

In regenerative medicine, there are various different materials suitable as implantable scaffolds. These can be fabricated from natural or synthetic materials. Common examples are polysaccharides (eg, chitosan), or polyesters (eg, poly e-caprolactone), for natural and synthetic polymers, respectively. However, they are both capable of degradation (either enzyme mediated, or hydrolysis) in vivo (Bassi et al., 2011 Cunha-Reis et al., 2007). Often, polyesters are used as implantable biodegradable biomaterials, as they have controllable degradation and mechanical properties through formation of block copolymers. Where degradation occurs, the scaffolds... 

Poly (fumerates) Biomaterials based on poly(propylene fiunerate) (PPF) have been extensively used for orthopedic application such as injectable bone cement [253]. Unlike PEGDA and pluronics, fiunerate-containing polymers are biodegradable since the ester fink in the polymers can be cleaved hydrolytically. PPF is hydrophobic, and in order to synthesize hydrogels, it has been... 

Our interest in the past few years has been on biodegradable polymers. We have been evaluating the potential of poly(phosphoesters) as degradable biomaterials (4).We were attracted to this class of polymers because the phosphoester bond in the backbone is cleavable under physiological conditions, the presence of the P-O-C group would facilitate fabrication, and the versatile chemical structure affords a wide... 

Nottelet B, Coudane J, Vert M (2006) Synthesis of an X-ray opaque biodegradable copolyester by chemical modiflcation of poly(E-caprolactone). Biomaterials 27 4948 954... 

Domb, A. J., Manor, N., Elmalak, O. (1996). Biodegradable bone cement compositions based on acrylate and epoxide terminated poly(propylene fumarate) oligomers and calcium salt compositions. Biomaterials, 77,411-417. 

Crommen, J.H.L., Schacht, E.H., and Mense, E.H.G. (1992). Biodegradable Polymers. 2. Degradation Characteristics of Hydrolysis-Sensitive Poly[(Qrgano)Phosphazenes]. Biomaterials, 13, 601-611. 

Bruin, P., Smedinga, J., Pennings, A.J., and Jonkman, M.E, Biodegradable lysine diisocyanate-based poly(glycolide-co-e-caprolactone)-urethane network in artificial skin. Biomaterials 11 191-295, 1990. 

Arote R, Kim TH, Kim YK et al (2007) A biodegradable poly(ester amine) based on polycaprolactone and polyethylenimine as a gene carrier. Biomaterials 28 735-744... 

Based on their behavior in living tissue, polymeric biomaterials can be divided into two groups biostable and biodegradable. Biostable polymers are used when permanent aids are needed, e.g., as prostheses [13]. Biostable polymers, typically polyethylene and poly(methyl methacrylate), should be physiologically inert in tissue conditions and maintain their mechanical properties for decades [11]. 

Bazile, D. V., Ropert, C., Huve, R, Verrecehia,T., Marlard, M., Frydman, A., Veillard, M., and Spenlehauer, G. (1992), Body distribution of fully biodegradable [14C]-poly(lactic acid) nanoparticles coated with albumin after parenteral administration to rats, Biomaterials, 13(15), 1093-1102. 

Jain, R. A. (2000), The manufacturing techniques of various drug loaded biodegradable poly(lactide-co-glycolide) (PLGA) devices, Biomaterials, 21(23), 2475-2490. 

M.C. Ilium, L. Long circulating biodegradable 68. poly(phosphazene) nanoparticles surface modified with poly(phosphazene)-poly(ethylene oxide) copolymer. Biomaterials 1997, 18, 1147-1152. 69. 

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