Carbon biocompatibility

Vitahium FHS ahoy is a cobalt—chromium—molybdenum ahoy having a high modulus of elasticity. This ahoy is also a preferred material. When combiaed with a properly designed stem, the properties of this ahoy provide protection for the cement mantle by decreasing proximal cement stress. This ahoy also exhibits high yields and tensile strength, is corrosion resistant, and biocompatible. Composites used ia orthopedics include carbon—carbon, carbon—epoxy, hydroxyapatite, ceramics, etc. 

Tessier, P. Y., Pichon, L., VUlechaise, P, Linez, P., Angleraud, B., MubumbUa, N., Fouquet, V, Straboni, A., Milhet, X., and Hildebrand, H. F., Carbon Nitride Thin Films as Protective Coatings for Biomaterials Synthesis, Mechanical and Biocompatibility Characterizations, Diamond Relat. Mater, Vol. 12,2003,pp. 1066-1069. 

C2-C4 w-alkanes [42,43], and in supercritical carbon dioxide when employing novel surfactants with fluorocarbon tails [38,44], There is also interest in the further employment of lipids (triglycerides and wax esters, such as isopropyl myristate) as solvent to improve biocompatibility [45],... 

Mutlu, G.M. et al. (2010) Biocompatible nanoscale dispersion of single-walled carbon nanotubes minimizes in vivo pulmonary toxicity. Nano Letters, 10 (5), 1664-1670. 

Carrero-Sanchez, J.C. et al. (2006) Biocompatibility and toxicological studies of carbon nanotubes doped withnitrogen. Nano Letters, 6 (8), 1609-1616. 

Liu, Z. et al. (2008) Circulation and longterm fate of functionalized, biocompatible single-walled carbon nanotubes in mice probed by Raman spectroscopy. Proceedings of the National Academy of Sciences of the U.S.A., 105 (5), 1410-1415. 

Fig. 1.14 (A) Single-wall carbon nanotubes wrapped by glyco-conjugate polymer with bioactive sugars. (B) Modification of carboxyl-functionalized single-walled carbon nanotubes with biocompatible, water-soluble phosphorylcholine and sugar-based polymers. (A) adapted from [195] with permission from Elsevier, and (B) from [35] reproduced by permission of Wiley-VCH.

It is interesting to compare halloysite with carbon nanotubes (Table 14.1). One can see that halloysite has some advantages in applications which require a biocompatible nano-container, in addition the halloysite clay is far less expensive, the world supply is in excess of50 000 tons per year. Carbon nanotubes have smaller diameter they may be conductive and they are very strong. 

In view of the conductive and electrocatalytic features of carbon nanotubes (CNTs), AChE and choline oxidases (COx) have been covalently coimmobilized on multiwall carbon nanotubes (MWNTs) for the preparation of an organophosphorus pesticide (OP) biosensor [40, 41], Another OP biosensor has also been constructed by adsorption of AChE on MWNTs modified thick film [8], More recently AChE has been covalently linked with MWNTs doped glutaraldehyde cross-linked chitosan composite film [11], in which biopolymer chitosan provides biocompatible nature to the enzyme and MWNTs improve the conductive nature of chitosan. Even though these enzyme immobilization techniques have been reported in the last three decades, no method can be commonly used for all the enzymes by retaining their complete activity. 

CNTs offer an exciting possibility for developing ultrasensitive electrochemical biosensors because of their unique electrical properties and biocompatible nanostructures. Luong et al. have fabricated a glucose biosensor based on the immobilization of GOx on CNTs solubilized in 3-aminopropyltriethoxysilane (APTES). The as-prepared CNT-based biosensor using a carbon fiber has achieved a picoamperometric response current with the response time of less than 5 s and a detection limit of 5-10 pM [109], When Nation is used to solubilize CNTs and combine with platinum nanoparticles, it displays strong interactions with Pt nanoparticles to form a network that connects Pt nanoparticles to the electrode surface. The Pt-CNT nanohybrid-based glucose biosensor... 

This chapter will describe the potential of carbon nanotubes in biomedicine. It will illustrate the methodologies to render nanotubes biocompatible, the studies on their cell uptake, their application in vaccine delivery, their interaction with nucleic acids and their impact on health. 

In recent years, CNTs have been receiving considerable attention because of their potential use in biomedical applications. Solubility of CNTs in aqueous media is a fundamental prerequisite to increase their biocompatibility. For this purpose several methods of dispersion and solubilisation have been developed leading to chemically modified CNTs (see Paragraph 2). The modification of carbon nanotubes also provides multiple sites for the attachment of several kinds of molecules, making functionalised CNTs a promising alternative for the delivery of therapeutic compounds. 

Carrero-Sanchez JC, Elias AL, Mancilla R, Arrellin G, Terrones H, Laclette JP, Terrones M (2006). Biocompatibility and toxicological studies of carbon nanotubes doped with nitrogen. Nano Lett. 6 1609-1616. 

Correa-Duarte MA, Wagner N, Rojas-Chapana J, Morsczeck C, Thie M, Giersig M (2004). Fabrication and biocompatibility of carbon nanotube-based 3D networks as scaffolds for cell seeding and growth. Nano Lett. 4 2233-2236. 

Shim M, Kam NMS, Chen RJ, Li R, Dai H (2002). Lunctionalization of carbon nanotubes for biocompatibility and biomolecular recognition. Nano Lett. 2 285-288. 

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