Gold nanopartides

Gold biochemistry has seen much development in recent years. The interaction of gold complexes with proteins and mitochondria, the possible role(s) of gold(III) in vivo, and the potential for developing future therapies using gold nanopartides are... 

Thompson, D.T. (2007) Using gold nanopartides for catalysis. Nano Today, 2, 40-Ai. 

Daniel, M.-C. and Astruc, D. (2004) Gold nanopartides assembly, supramolecular chemistry, quantum-size-related properties, and applications toward biology, catalysis, and nanotechnology. Chemical Reviews, 104, 293-346. 

Yamamoto, Y Miura, T Suzuki, M., Kawamura, N Miyagawa, H Nakamura, T Kobayashi, K Teranishi, T. and Hori, H. (2004) Direct observation of ferromagnetic spin polarization in gold nanopartides. Physical Review Letters, 93, 116801. 

Compton, O.C. and Osterloh, F.E. (2007) Evolution of size and shape in the colloidal crystallization of gold nanopartides. Journal of the American Chemical Society, 129, 7793-7798. 

Lin, S.-Y, Wu, S.-H. and Chen, C.-H. (2006) A simple strategy for prompt visual sensing by gold nanopartides general applications of interpartide hydrogen bonds. Angewandte Chemie International Edition, 45, 4948 951. 

Oonishi, T., Sato, S., Yao, H. and Kimura, K. (2007) Three-dimensional gold nanopartide superlattices Structures and optical absorption characteristics. Journal of Applied Physics, 101, 114314. 

El-Sayed, I.H., Huang, X. and El-Sayed, M.A. (2005) Surface plasmon resonance scattering and absorption of anti-EGFR antibody conjugated gold nanopartides in cancer diagnostics Applications in oral cancer. Nano Letters, 5, 829-834. 

Liquid crystal gold nanopartides that exhibit a thermotropic nematic phase in the bulk have been reported recently (Figure 8.28). 

The nematic nanoparticies have been prepared by a two step synthetic process. First, gold nanopartides are covered with an alkylthiol monolayer (hexyl- and dodecylthiol) in a second step, the alkylthiol-nanoparticles are reacted with the functionalized thiol mesogen in dichloromethane at room temperature to obtain the monolayer-protected liquid crystal gold nanopartides. These materials are chemically stable and display a nematic mesophase at room temperature [67, 68]. Other examples include liquid crystal gold nanopartides functionalized by hexaalkoxy-substituted triphenylene [69]. 

Several mixtures of hexanethiol capped gold nanopartides and triphenylene based discotic LCs have been studied. These mixtures display liquid crystal behavior (columnar mesophases) and an enhancement in the DC conductivity, due to the inclusion of gold nanoparticies into the matrix of the organic LC [70]. Other studies of mixtures of gold nanoparticies with mesogens indude a series of cholesteryl phenoxy alkanoates. The inclusion of the nanopartides does not change the inherent liquid crystal properties of the cholesteryl derivative but the mesophases are thermally stabilized [71]. 

Dobbs, W., Suisse, J.-M., Douce, L. and Welter, R. (2006) Electrodeposition of Silver Partides and Gold Nanopartides from Ionic Liquid-Crystal Precursors. Angewandte Chemie (International Edition in English), 45, 4179-4182. 

Cseh, L. and Mehl, G.H. (2007) Structure-property relationships in nematic gold nanopartides. Journal of Materials Chemistry, 17, 311-315. 

Yamada, M., Shen, Z. and Miyake, M. (2006) Self-assembly of discotic liquid crystalline molecule-modified gold nanopartides control of ID and hexagonal ordering induced by solvent polarity. Chemical Communications, (24), 2569-2571. 

Kumar, S., Pal, S.K. and Lakshminarayanan, V. (2005) Discotic-Decorated Gold Nanopartides. 

Qi, H. and Hegmann, T. (2006) Formation of periodic stripe patterns in nematic liquid crystals doped with functionalized gold nanopartides. Journal of Materials Chemistry, 16, 4197-4205. 

Donnio, B., Garcia-Vazquez, P., Gallani, J.-L., Guillon, D. and Terazzi, E. (2007) Dendronized Ferromagnetic Gold Nanopartides Self-Organized in a Thermotropic Cubic Phase. Advanced Materials, 19, 3534-3539. 

Hohenau, A., Krenn, J. R., Schider, G., Ditlbacher, H., Leitner, A., Aussenegg, F. R. and Schaich, W. L. (2005) Optical nearfield of multipolar plasmons of rodshaped gold nanopartides. Europhys. Lett., 69, 538-543. 

Brust, M., Walker, M., Bethell, D., Schiffrin, D.J. and Whyman, R. (1994) Synthesis of thiol-derivatized gold nanopartides in a 2-phase liquid—liquid system. Journal of the Chemical Society, Chemical Communications (7), 801—802. 

Link, S. and El-Sayed, M.A. (1999) Size and temperature dependence of the plasmon absorption of colloidal gold nanopartides. Journal of Physical Chemistry B, 103 (21), 4212—4217. 

Metallic nanoparticles have been synthesized in vivo using plants. Intracellular synthesis of gold nanopartides was demonstrated using the sweet desert willow (Chilopsis linearis) plant [95]. The average size of Au nanopartides formed in various tissues was dependent on the concentration of Au in the respective tissues. Haver-kamp et al. [96] synthesized a gold-silver-copper alloy in vivo using the Brasskajuncea plant. 

Regev, D., Backov, R. and Faure, C. (2004) Gold nanopartides spontaneously generated in onion-type multilamellar vesides bilayers. Particle coupling imaged by cryo-TEM. Chemistry of Materials, 16, 5280-5285. 

R. (2001) Bioreduction of AuCLt- ions by the fungus VerticiUium sp. and surface trapping of the gold nanopartides formed. Angewandte Chemie-Intemational Edition, 40, 3585-3588. 

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