Carbon Nanotube biocompatibility

Garibaldi S, Brunelli C, Bavastrello V, Ghigliotti G, Nicolini C (2006) Carbon nanotube biocompatibility with cardiac muscle cells. Nanotechnology 17 391-397. 

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. 

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. 

Pharmacological Applications of Biocompatible Carbon Nanotubes and Their Emerging Toxicology Issues ... 

Keywords carbon nanotubes, biomaterials, biocompatibility, toxicity, nanomaterials... 

Nanocarbon structures such as fullerenes, carbon nanotubes and graphene, are characterized by their weak interphase interaction with host matrices (polymer, ceramic, metals) when fabricating composites [99,100]. In addition to their characteristic high surface area and high chemical inertness, this fact turns these carbon nanostructures into materials that are very difficult to disperse in a given matrix. However, uniform dispersion and improved nanotube/matrix interactions are necessary to increase the mechanical, physical and chemical properties as well as biocompatibility of the composites [101,102]. 

D. H. Zhang, M. A. Kandadai, J. Cech, S. Roth, S. A. Curran, Poly(L-lactide) (PLLA)/multiwalled carbon nanotube (MWCNT) composite Characterization and biocompatibility evaluation, Journal of Physical Chemistry B, vol. 110, pp. 12910-12915, 2006. 

B. Sitharaman, X.F. Shi, X.F. Walboomers, H.B. Liao, V. Cuijpers, L.J. Wilson, A.G. Mikos, J.A. Jansen, In vivo biocompatibility of ultra-short single-walled carbon nanotube/biodegradable polymer nanocomposites for, bone tissue engineering, Bone, vol. 43, pp. 362-3Z0, 2008. 

Apart from the promising electrochemical properties that will be exhaustively discussed through this chapter, carbon nanotubes have become a hot research topic due to their outstanding electronic, mechanical, thermal, optical and chemical properties and their biocompatibility. Near- and long-term innovative applications can be foreseen including nanoelectronic and nanoelectromechanical devices, held emitters, probes, sensors and actuators as well as novel materials for mechanical reinforcement, fuel cells, batteries, energy storage, (bio)chemical separation, purification and catalysis [20]. 

Carbon nanotubes are unique materials with specific properties [42]. There is a considerable application potential for using nanotubes in the biomedical field. However, when such materials are considered for application in biomedical implants, transport of medicines and vaccines or as biosensors, their biocompatibility needs to be established. Other carbon materials show remarkable long-term biocompatibility and biological action for use as medical devices. Preliminary data on biocompatibility of nanotubes and other novel nanostructured materials demonstrate that we have to pay attention to their possible adverse effects when then-biomedical applications are considered. 

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