Protein nanotube

Kam NWS, JessopTC, WenderPA, Dai HJ (2004)Nanotubemoleculartransporters Internalization of carbon nanotube-protein conjugates into mammalian cells. J. Am. Chem. Soc. 126 6850-6851. 

Table 2.3 Applications of carbon nanotube-protein bioconjugates.

Nanoparticles, as it is discussed before, are a very versatile group of nanomaterials. The different types of materials possess different properties, which, in combination with the different types of biomacromolecules immobilized onto their surface, can lead to a variety of applications. As discussed in Section 2.3 on carbon nanotubes, proteins, nucleic acids, antigens, peptides and drugs, can interact and be immobilized onto nanoparticles. 

Ciofani, G. Del Turco, S. Genchi, G. G. D Alessandro, D. Basta, G. Mattoli, V. Transferrin-conjugated boron nitride nanotubes Protein grafting, characterization, and interaction with human endothelial cells. Int. J. Pharm. 2012, 436,444-453. 

Wei G, Zhang J et al (2011) Biomimetic growth of hydroxyapatite on super wato-soluble carbon nanotube-protein hybrid nanofibers. Carbon 49(7) 2216-2226... 

Figure 17.4 Cartoon representation of strategies for studying and exploiting enzymes on electrodes that have been used in electrocatalysis for fuel cells, (a) Attachment or physisorption of an enzyme on an electrode such that redox centers in the protein are in direct electronic contact with the surface, (b) Specific attachment of an enzyme to an electrode modified with a substrate, cofactor, or analog that contacts the protein close to a redox center. Examples include attachment of the modifier via a conductive linker, (c) Entrapment of an enzyme within a polymer containing redox mediator molecules that transfer electrons to/from centers in the protein, (d) Attachment of an enzyme onto carbon nanotubes prepared on an electrode, giving a large surface area conducting network with direct electron transfer to each enzyme molecule.

Gooding JJ, Wibowo R, Liu JQ, Yang WR, Losic D, Orbons S, Meams FJ, Shapter JG, Hibbert DB. 2003. Protein electrochemistry using aligned carbon nanotube arrays. J Am Chem Soc 125 9006-9007. 

Witzmann, A.F. and Monteiro-Riviere, N.A. (2006) Multi-walled carbon nanotube exposure alters protein expression in human keratinocytes. Nanomedicine, 2 (3), 158—168. 

Kam, N.W.S. and Dai, H.J. (2005) Carbon nanotubes as intracellular protein transporters generality and biological functionality. Journal of the American Chemical Society, 127 (16), 6021-6026. Heller, D.A. et al. (2005) Single-walled carbon nanotube spectroscopy in live cells towards long-term labels and optical sensors. Advanced Materials, 17 (23), 2793-2799. 

Such carbonyls may be further oxidized using potassium permanganate (KMnO and perchloric acid (HCIO4) to convert all of these groups into carboxylic acids. Once functionalized in this manner, the nanotubes can be fully dispersed in aqueous systems. Kordas et al. (2006) used these derivatives to print nanotube patterns on paper or polymer surfaces to create conductive patterns for potential use in electronic circuitry. The carboxylates also may be used as conjugation sites to link other ligands or proteins to the nanotube surface using a carbodiimide reaction as previously discussed (Section 1, this chapter Chapter 2, Section 1.11 Chapter 3, Section 1). 

Figure 15.13 Tween 20 can be activated with CDI using its hydroxyl groups to create an amine-reactive imidazole carbamate intermediate that then can be used to coat a carbon nanotube. The result is an activated nanotube that can be used to couple proteins and other amine-containing molecules.

Resuspend the activated nanotubes in the ligand-containing carbonate buffer and react with mixing overnight at room temperature or 4°C (e.g., for sensitive proteins). 

Maehashi, K., Katsura, T., Kerman, K., Takamura, Y., Matsumoto, K., and Tamiya, E. (2007) Label-free protein biosensor based on aptamer-modified carbon nanotube field-effect transitors. Anal. Chem. 79, 782-787. 

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