Silver nanoparticles formation

The initial report of microbial synthesis of nanoparticles was on intracellular silver nanoparticle formation in Pseudomonas stutzeri AG259, which was isolated from... 

FIGURE 28.1 Time courses of silver nanoparticle formation obtained with 1 mM AgNOj and 5% Magnolia kobus leaf broth with different reaction temperatures. 

Van Hyning D.L., KlempCTo- W.G., Zukoski C.F. Silver nanoparticle formation Predictions and verification of the aggregative growth model. Langmuir. 2001b 17(11) 3128-3135 van der Awschot E., Mewis J.A. Equilibrium properties of reversibly flocculated dispersions. Colloids Surf. 1992 69(1) 15-22... 

The production of fatty acid-capped silver nanoparticles by a heating method has been reported [115]. Heating of the silver salts of fatty acids (tetradecanoic, stearic, and oleic) under a nitrogen atmosphere at 250°C resulted in the formation of 5-20-nm-diameter silver particles. Monolayers of the capped particles were spread from toluene and transferred onto TEM grids. An ordered two-dimensional array of particles was observed. The oleic acid-capped particle arrays had some void regions not present for the other two fatty acids. 

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]. 

Socol Y, Abramson O, Gedanken A et al (2002) Suspensive electrode formation in pulsed sonoelectrochemical synthesis of silver nanoparticles. Lagmuir 18 4736-4740... 

Salkar et al. [51] reported the formation of amorphous silver nanoparticles of approximately 20 nm size by the sonochemical reduction of an aqueous solution of silver nitrate in an atmosphere of argon-hydrogen [in the ratio of 95 5] at 10°C. Formation of silver nanoparticles, according to them was through the generation of radical species - as a primary reaction. 

Faure, C., Derre, A. and Neri, W. (2003) Spontaneous formation of silver nanoparticles in multilamellar vesicles. Journal of Physical Chemistry B, 107, 4738-4746. 

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. 

In this chapter, we discuss first how the silver clusters relate to silver atoms and silver nanoparticles. Then we overview the formation of fluorescent silver clusters in aqueous solution, using silver salts as precursors and various scaffolds as stabilizers. Finally we discuss applications of silver clusters in fluorescent labeling of biological tissues, and their use as fluorescent probes for sensing of molecules. 

A commonly used staining method for the cell nucleolus is based on silver nanoparticles [54], The proteins of the nucleolus, such as nucleolin, are known to have high affinity to silver ions due to their amino-terminal domain. Subsequent reduction leads to the formation of the silver nanoparticles stain. In spite of all the efforts, a general and definitive conclusion regarding the attraction between silver... 

The major issue is the formation of silver clusters in situ in the presence of the biomolecule to be labeled. On one hand, this problem is due to the fact that only a few scaffolds are suitable systems providing the proper environment for the formation of these very small species and preventing the formation of larger silver nanoparticles. On the other hand, the biomolecules might be harmfully... 

Bale SS, Asuri P, Karajanagi SS, Dordick JS, Kane RS (2007) Protein-directed formation of silver nanoparticles on carbon nanotubes. Adv. Mater. 19 3167-3170. 

Li et al. reported first on the decoration of hydrothermal carbon spheres obtained from glucose with noble metal nanoparticles [19]. They used the reactivity of as-prepared carbon microspheres to load silver and palladium nanoparticles onto then-surfaces, both via surface binding and room-temperature surface reduction. Furthermore, it was also demonstrated that these carbon spheres can encapsulate nanoparticles in their cores with retention of the surface functional groups. Nanoparticles of gold and silver could be encapsulated deep in the carbon by in situ hydrothermal reduction of noble-metal ions with glucose (the Tollens reaction), or by using silver nanoparticles as nuclei for subsequent formation of carbon spheres. Some TEM images of such hybrid materials are shown in Fig. 7.4. 

The direct LbL assembly of oppositely charged nanoparticles, which did not involve polyelectrolytes, was also examined. Sastry et al. demonstrated the formation of alternating layers of gold and silver nanoparticles via sequential electrostatic assembly.36 In the absence of polyelectrolytes, the effective charging of gold and silver nanoparticles was accomplished by the adsorption of 4-aminothiophenol and 4-carboxythiophenol molecules on the nanoparticle surfaces, respectively. The multilayer films were stable up to 100°C. 

Xu H, Xu 1, Zhu Y, Liu H, Liu S (2006) In situ formation of silver nanoparticles with tunable spatial distribution at the poly(A-isopropylacrylamide) corona of unimolecular micelles. Macromolecules 39 8451-8455... 

Reported volume resistivities for printed patterns formed from commercial silver-based inks are higher than that of bulk silver. This occurrence reflects the fact that sintered ink patterns contain non-ideal defects such as incomplete particle-to-particle contact, incomplete sintering between contacting particles, residual porosity, and the presence of non-conductive additives. The morphology and extent of void formation in two representative sintered silver nanoparticle inkjet inks are illustrated in Fig. 1. 

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