Biomedical materials improvement

Meng J, Kong H, Xu HY, Song L, Wang CY, Xie SS (2005) Improving the blood compatibility of polyurethane using carbon nanotubes as fillers and its implications to cardiovascular surgery. Journal of Biomedical Materials Research Part A 74A 208-214. 

The field of biomedical materials has grown rapidly over the past 20 years and offers solutions to repair defects, correct deformities, replace damaged tissue and provide therapy. This has contributed to the increase in the average lifetime of individuals in developed countries. The market value for biomaterials is of the order of billions of dollars per annum worldwide and is growing as new products offer improved performance or provide new solutions health problems. Apatites are playing a key role in biomedical implants. 

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... 

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. 

Ju, Y.M., Yu, B., West, L., Moussy, Y, Moussy, F., 2010. A novel porous collagen scaffold around an implantable biosensor for improving biocompatibility. II. Long-term in vitro/ in vivo sensitivity characteristics of sensors with NDGA- or GA-crosslinked collagen scaffolds. Journal of Biomedical Materials Research Part A 92, 650-658. 

Another synthetic polymer used in combination with PVA, in order to improve its properties, is poly(ethylene glycol) (PEG) (Martens et al. 2003 Mansur et al. 2004 Dutta 2012). This is a water-soluble, biocompatible, biodegradable, transparent, and viscous polymer that has been used in the industrial manufacturing of biomedical materials. 

ZHU 03] Zhu Y., Gao C., Guan J. et al., Engineering porous polyurethane scaffolds by photo grafting polymerization of methacrylic acid for improved endothelialcell compatibility , Journal of Biomedical Materials Research Part vol. 67A, pp. 1367-1373, 2003. 

Society for Biomaterials http //biomaterials.org/ (accessed September 17,2010). The Society for Biomaterials is a professional society that promotes advances in biomedical materials research and development by encouragement of cooperative educational programs, clinical applications, and professional standards in the biomaterials field. Biomaterials scientists and engineers study cells, their components, complex tissues and organs and their interactions with natural and synthetic materials and implanted prosthetic devices, as well as develop and characterize the materials used to measure, restore, and improve physiologic function, and enhance survival and quality of life (from Web page). 

HAp nanoparticles were adsorbed equally and dispersively on the treated SF fibre surface by ionic interactions. This synthetic system requires no heat to connect HAp to SF and is useful when applying to non-heat-resistant biomedical materials. The cell-adhesion test shows that the SF/HAp composites improves bioactivity compared to the original SF, and that they do not cause inflammation in living bodies. 

Other related areas include the creation of new biocompatible dehvery systems for cellular therapy and agricultural fertilizers [22, 23]. It has been suggested that nanophase calcium phosphates can mimic the dimensions of constituent components of natural tissues, and consequently nanocalcium phosphates can be utihzed for tissue-engineered implants with improved biocompatibility [24]. In this respect, it is the development of calcium phosphate biomedical materials that stands to benefit most from such nanotechnology. 

Brown, J.L., et al., 2010. Composite scaffolds bridging nanofiber and microsphere architectures to improve bioactivity of mechanically competent constructs. Journal of Biomedical Materials Research. Part A 95 (4), 1150-1158. Available at http //www.ncbi.nlm.nih.gov/ pubmed/20878987 (accessed 10.10.14.). 

Nichols, H.L., Zhang, N., Zhang, J., Shi, D., Bhaduri, S., Wen, X., 2007. Coating nanothickness degradable films on nanocrystaUine hydroxyapatite particles to improve the bonding strength between nanohydroxyapatite and degradable polymer matrix. Journal of Biomedical Materials Research Part A 82A, 373-382. 

Matsiko, A., Levingstone, T.J., O Brien, E.J., Gleeson, J.P., 2012. Addition of hyaluronic acid improves cellular infiltration and promotes early-stage chondrogenesis in a coUagen-based scaffold for cartilage tissue engineering. Journal of the Mechanical Behavior of Biomedical Materials 11, 41-52. 

Ma, Z., Gao, C., Gong, Y, Shen, J., 2003. Paraffin spheres as porogen to fabricate poly(L-lactic acid) scaffolds with improved cytocompatibihty for cartilage tissue engineering. Journal of Biomedical Materials Research Part B Applied Biomaterials 67, 610-617. 

Childs, A., Hemraz, U.D., Castro, NJ., Fenniri, H., Zhang, L.G., 2013. Novel biologicaUy-inspired rosette nanotuhe PLLA scaffolds for improving human mesenchymal stem cell chondrogenic differentiation. Biomedical Materials 8,065003. 

We use the following natural polymers either directly or after physical and/or chemical conversions diat aim at improving upon their properties or adding to characteristics. Natural polymers are derived fi om plants, animals and microorganisms, besides finding extensive use as food, many natural polymers are used as materials in applications ranging fi om construction and clothing to biomedical materials. 

Improved characterization of the morphological/microstructural properties of porous solids, and the associated transport properties of fluids imbibed into these materials, is crucial to the development of new porous materials, such as ceramics. Of particular interest is the fabrication of so-called functionalized ceramics, which contain a pore structure tailored to a specific biomedical or industrial application (e.g., molecular filters, catalysts, gas storage cells, drug delivery devices, tissue scaffolds) [1-3]. Functionalization of ceramics can involve the use of graded or layered pore microstructure, morphology or chemical composition. 

Apart from modifications in the bulk, also surface modification of PHAs has been reported. Poly(3HB-co-3HV) film surfaces have been subjected to plasma treatments, using various (mixtures of) gases, water or allyl alcohol [112-114]. Compared to the non-treated polymer samples, the wettability of the surface modified poly(3HB-co-3HV) was increased significantly [112-114]. This yielded a material with improved biocompatibility, which is imperative in the development of biomedical devices. 

The main goal when synthesising a silicate-containing hybrid material for any application, including biomedical ones, is to take advantage of both domains to improve the final properties. Table 12.1 collects some of the features that each domain can supply to the hybrid. The final properties are not only the addition of the... 

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