Biomedical materials poly

This chapter is devoted to a miscellaneous group of aqueous acid-base cements that do not fit into other categories. There are numerous cements in this group. Although many are of little practical interest, some are of theoretical interest, while others have considerable potential as sustained-release devices and biomedical materials. Deserving of special mention as biomedical materials of the future are the recently invented polyelectrolyte cements based on poly(vinylphosphonic adds), which are related both to the orthophosphoric acid and poly(alkenoic add) cements. 

Zhang, R. and Ma, P.X. (1999) Porous poly(L-lactic acid)/apatite composites created by biomimetic process. Journal of Biomedical Materials Research, 45, 285-293. 

Rhee, S.H. (2003) Effect of calcium salt content in the poly(e-caprolactone)/ silica nanocomposite on the nudeation and growth behavior of apatite layer. Journal of Biomedical Materials Research, 67A,1131-1138. 

Roberts, J., Bhalgat, M. and Zera, R. T. (1996) Preliminary evaluation of poly-amidoamine (PAMAM) starburst dendrimers. J. Biomedical. Materials Res., 30, 53 (1996). 

Some of the most useful polyphosphazenes are fluoroalkoxy derivatives and amorphous copolymers (11.27) that are practicable as flame-retardant, hydrocarbon solvent- and oil-resistant elastomers, which have found aerospace and automotive applications. Polymers such as the amorphous comb polymer poly[bis(methoxyethoxyethoxy)phosphazene] (11.28) weakly coordinate Li " ions and are of substantial interest as components of polymeric electrolytes in battery technology. Polyphosphazenes are also of interest as biomedical materials and bioinert, bioactive, membrane-forming and bioerodable materials and hydrogels have been prepared. 

The use of synthetic polymers in medicine and biotechnology is a subject of wide interest. Polymers are used in replacement blood vessels, heart valves, blood pumps, dialysis membranes, intraocular lenses, tissue regeneration platforms, surgical sutures, and in a variety of targeted, controlled drug delivery devices. Poly(organosiloxanes) have been used for many years as inert prostheses and heart valves. Biomedical materials based on polyphosphazenes are being considered for nearly all the uses mentioned above. 

Kao WJ, McNally AK, Hiltner A, Anderson JM. Role for interleukin4 in foreign-body giant cell formation on a poly(etherurethane urea) in vivo. Journal of Biomedical Materials Research 1995, 29, 1267-1275. 

Voskerician G, Gingras PH, Anderson JM. Macroporous condensed poly (tetrafluoroethylene). I. In vivo inflammatory response and healing characteristics. Journal of Biomedical Materials Research A 2006, 76, 234—242. 

Aging-resistance. Aging-resistance specifically describes the capacity of materials to resist critical stress-induced cracking. The majority of plastics or elastomers are lacking in aging-resistance, except for biomedical-grade poly (ether urethanes) and their derivative products. 

Kosdiwanez, H.E., Yap, F.Y., Klitzman, B., and Reichert, W.M. (2008) In vitro and in vivo characterization of porous poly-L-lactic add coatings for subcutaneously implanted glucose sensors. Journal of Biomedical Materials ResearchPart A, 87A (3), 792-807. 

Chitin is known to be biodegradable, biocompatible, and nontoxic. It is used in dmg delivery and bio medical applications. It also used in the purification of water especially for the absorption of toxic dyes. Chitin has limited solubility in solvents but chitosan is readily soluble in acidic aqueous solutions and has more tendency to be chemically modified. Chitosan can readily be spun into fibers, cast into films, or precipitated in a variety of micromorphologies from acidic solutions. Min and Kim have reported on the adsorption of acid dyes from wastewater using composites of PAN/chitosan [52]. Shin et al. has reported on copolymers composed of PVA and poly dimethyl siloxanes cross-linked with chitosan to prepare semi IPN hydrogels for application as biomedical materials... 

Tyler, B.J., B.D. Ratner, and D.G. Castner, Variations between Biomer lots. I. Significant differences in the surface chemistry of two lots of a commercial poly (ether urethane). Journal of Biomedical Materials Research, 1992, 26, 273-289. 

Kulkarni, R.K., et al. Biodegradable poly(lactic acid) polymers. Journal of Biomedical Materials Research, 1971, 5, 169-181. 

Ertel, S.I. and J. Kohn, Evaluation of poly(DTH carbonate) a tyrosine-derived degradable polymer, for orthopedic applications. Journal of Biomedical Materials Research, 1995, 29, 1337-1348. 

Pinchuk, L., E.C. Eckstein, and M.R. Van De Mark, The interaction of urea with the generic class of poly(2-hydroxyethyl methacrylate) hydrogels. Journal of Biomedical Materials Research, 1984, 18, 671-684. 

Another challenge in the biomedical materials area is the search for synthetic materials with Improved blood compatibility for artificial heart devices and other organs. An early study by Wade (24) using a series of poly(organophosphazenes) showed these polymers in the unfilled state are as blocompatlble as silicon materials. More recent blood compatibility studies using radiation crossllnked PNF showed excellent hemo compatibility... 

Hua, F.J., Kim, G.E., Lee, J.D., Son, Y.K., Lee, D.S., 2002. Macroporous poly(L-lactide) scaffold 1. Preparation of a macroporous scaffold by liquid—Uquid phase separation of a PLLA—dioxane—water system. Journal of Biomedical Materials Research 63, 161—167. 

Lu, L., Garcia, C. A., Mikos, A. G. In vitro degradation of thin poly(DL-lactic-co-glycolic acid) films. Journal of Biomedical Materials Research. 1999, 46, 236-244. 

Scholz, C. Poly(y -hydroxyaIkanoates) as potential biomedical materials an overview. In Scholz, C., Gross, R.A. (eds.) Polymers from renewable lesources-biopolymers and biocatalysis, ACS series, vol. 764, pp. 328-334 (2000)... 

Kim, H. Y. Yasuda, H. K. (1999) Improvement of fatigue properties of poly(methyl methacrylate) bone cement by means of plasma surface treatment of fillers. Journal of Biomedical Materials Research, 48, 135-142. 

Matsuda, T. Mizutani, M. (2002) Liquid acrylate-endcapped biodegradable poly(epsilon-caprolactone-co-trimethylene carbonate). II. Computer-aided stereolithographic microarchitectural surface photoconstructs. Journal of Biomedical Materials Research, 62, 395—403. 

Patel, P. N., Smith, C. K. Patrick, C. W. (2005) Rheological and recovery properties of poly(ethylene glycol) diacrylate hydrogels and human adipose tissue. Journal of Biomedical Materials Research Part A, 73A, 313-319. 

Peter, S. J., Miller, S. T., Zhu, G. M., Yasko, A. W. Mikos, A. G. (1998) In vivo degradation of a poly(propylene fiimarate) beta-tricalcium phosphate injectable composite scaffold. Journal of Biomedical Materials Research, 41, 1-7. 

Topoleski, L. D. T., Ducheyne, P. Cuckler, J. M. (1995) The effects of centrifugation and titanium fiber reinforcement on fatigue failure mechanisms in poly(methyl methacrylate) bone-cement. Journal of Biomedical Materials Research, 29, 299-307. 

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