Plants nanoparticle formation

Gold Nanoparticles Formation by Living Alfalfa Plants... 

V. Armendariz, Bioreduction of Gold(III) to Gold(O) and Nanoparticle Formation by Oat and Wheat Biomasses The Use of Plants in Nanobiotechnology. Master Thesis, the University of Texas at El Paso, Chemistry Department, El Paso, TX, 2005, p. 107. 

Gardea-Torresdey, J. 2003. Use of XAS and TEM to determine the uptake of gold and silver and nanoparticle formation by living alfalfa plants. Abstracts of Papers of the American Chemical Society 225 U837-U837. 

FIGURE 2.10 Transmission electron microscopy images of silver nanoparticles from plant samples irrigated with (a) 10 g/L Ag as AgNOj and (b) 10 g/L Ag as Ag(NH3)2N03. (With kind permission from Springer Science + Business Media from Journal of Nanoparticle Research, Haverkamp and Marshall. The mechanism of metal nanoparticle formation in plants Limits on accumulation, 11, 2008, 1453-1463.)... 

Pioneering studies by Gardea-Torresdey et al. [28,29] reported for the first time the formation of gold and silver nanoparticles by living plants. Their study demonstrated that alfalfa plants can form gold and silver nanoparticles. Furthermore, these researchers reported that nucleation/ growth of the metallic nanoparticles took place inside the plants. This study opened new and exciting ways to synthesize metallic nanoparticles [30,31]. 

Gardea-Torresdey, J. L. Parsons, J. G. Gomez, E. Peralta-Videa, J. Troiani, H. E. Santiago, R Jose Yacaman, M. 2002. Formation and growth of Au nanoparticles inside live alfalfa plants. Nano Lett. 2 397 101. 

The production of nanoparticles was done by mixing of salt and various plant sources of extracts to maintain the exact size, shape, and morphological features by varying several conditions like pH, temperature, concentration of metal salt, reaction time, reaction medium, etc. by maintaining these parameters one can synthesize metal nanoparticles in a required morphological formation (Madhumitha and Roopan, 2013). 

Sometimes, also polynuclear clusters such as Rh4(CO)j2 or Rh6(CO)26 were submitted to the formation of rhodium catalysts [18]. Metallic rhodium embedded in inorganic materials (carbon, AI2O3) was tested for mini-plant manufacturing. In this context, the frequently phosphorus ligands [PPhj, P(OPh)3] were added with the intention to detach rhodium from the heterogeneous layer (activated rhodium catalyst = ARC) [19, 20] More recently, ligand (Xantphos, PPhj, BIPHEPHOS)-modified or unmodified rhodium(O) nanoparticles were used as catalyst precursors for solventless hydroformylation [21]. It is assumed that under the reaction conditions these metal nanoparticles decompose and merge into soluble mononuclear Rh species, which in turn catalyze the hydroformylation. 

A new reducing agent (one of the natural plant pigments, quercetin, Qr) for the synthesis of Ag nanoparticles in reverse micelles was reported to generate highly stable and rather monodisperse particles [311]. It was reported that apart from its strong interaction with performed nanoparticles, Qr reduces silver ions from aqueous salt solutions, presumably through the formation of an intermediate complex where electron density is shifted towards the silver ion. 

Armendariz, V., Herrera, 1., Peralta-Videa, ).R., )ose-Yacaman, M., Troiani, H., Santiago, P. and Gardea-Torresdey, ).L. (2004) Size controlled gold nanopartide formation by Avena sativa biomass use of plants in nanobiotechnology. Journal of Nanoparticle Research, 6, 377-82. 

In the case of lemongrass extracts, aqueous solutions of tetrachloroaurate were reacted with the plant extract, which resulted in the formation of colloidal gold solutions [71]. The formation of gold nanoparticles was confirmed by UV-visible data, which showed the presence of plasmon resonance at approximately 530 nm in the reaction solutions. A TEM analysis revealed the nanoparticles to be nano-... 

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