Methods for Synthesis of Colloidal Gold

Handley, Dean A.

doi:10.1016/b978-0-12-333927-0.50007-6

Cited by 115 publications

(97 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…During the formation of the metallic sol and the storage time, a huge excess of NaOH is present. THPC/NaOH, acts as the reducing agent by the formation of formaldehyde, a wellknown reducing agent for gold under basic conditions, [23] following the mechanism: [24] P(CH 2 OH) 4…”

Section: Resultsmentioning

confidence: 99%

Gold Sols as Catalysts for Glycerol Oxidation: The Role of Stabilizer

Villa

Wang

et al. 2009

ChemCatChem

View full text Add to dashboard Cite

Gold nanoparticles (Au NPs), stabilized by polyvinylalcohol (PVA), tetrakishydroxypropylphosphonium chloride (THPC), and citrate, have been synthesized and tested in the liquid‐phase oxidation of glycerol. THPC‐stabilized Au NPs have been found to exhibit remarkable catalytic activity (TOF=2478 h−1) in comparison to PVA‐ and citrate‐stabilized nanoparticles (TOF=715 and 160 h−1, respectively). The catalytic results can be explained in terms of particle size but aging treatment also revealed the influence of the protective agent. PVA as stabilizer produced small and quite stable gold nanoparticles differently from the THPC system. However PVA also limits the accessibility of reactant to the active site.

show abstract

Section: Resultsmentioning

confidence: 99%

Gold Sols as Catalysts for Glycerol Oxidation: The Role of Stabilizer

Villa

Wang

et al. 2009

ChemCatChem

View full text Add to dashboard Cite

show abstract

“…The FSF procedure described above was modified to include a preembedding gold-enlarging technique for HPF cells by adapting approaches that involve silver or gold enhancement at room temperature (Danscher, 1981;Hacker et al, 1988;Hainfeld and Furuya, 1995;Scopsi, 1989), gold-toning (Sawada and Esaki, 2000), seed-mediated gold-enlarging (Busbee et al, 2003;Daniel and Astruc, 2004;Gole and Murphy, 2004;Handley, 1989;Jana et al, 2001;Meltzer et al, 2001;Okitsu et al, 2005;Zou et al, 2006) and a FSF-based silver-enhancement procedure (Morphew et al, 2007). To avoid the background that results from spontaneous autonucleation, we designed a three-step enlarging protocol in which silver enhancement was used to slightly enlarge the Nanogold, the silver shell was coated by gold toning to make it insoluble in osmium, and the particles were further enlarged to 10 -16 nm using gold enhancement.…”

Section: Silver Enhancement/gold-toning/gold Enhancement During Fsf Omentioning

confidence: 99%

A freeze substitution fixation-based gold enlarging technique for EM studies of endocytosed Nanogold-labeled molecules

Kivork

Machinani

et al. 2007

Journal of Structural Biology

View full text Add to dashboard Cite

We have developed methods to locate individual ligands that can be used for electron microscopy studies of dynamic events during endocytosis and subsequent intracellular trafficking. The methods are based on enlargement of 1.4 nm Nanogold attached to an endocytosed ligand. Nanogold, a small label that does not induce misdirection of ligand-receptor complexes, is ideal for labeling ligands endocytosed by live cells, but is too small to be routinely located in cells by electron microscopy. Traditional pre-embedding enhancement protocols to enlarge Nanogold are not compatible with high pressure freezing/freeze substitution fixation (HPF/FSF), the most accurate method to preserve ultrastructure and dynamic events during trafficking. We have developed an improved enhancement procedure for chemically-fixed samples that reduced autonucleation, and a new pre-embedding goldenlarging technique for HPF/FSF samples that preserved contrast and ultrastructure and can be used for high-resolution tomography. We evaluated our methods using labeled Fc as a ligand for the neonatal Fc receptor. Attachment of Nanogold to Fc did not interfere with receptor binding or uptake, and gold-labeled Fc could be specifically enlarged to allow identification in 2D projections and in tomograms. These methods should be broadly applicable to many endocytosis and transcytosis studies.

show abstract

“…Ostwald (18) reported that tannin can reduce chloroauric acid at neutral pH to form stable gold nanoparticles even if tap water is used to prepare the aqueous solutions. Tannic acid is also an important constituent of the widely used Slot and Geuze protocol (19) for synthesizing gold nanoparticles in the size range of 3-17 nm with nominal standard deviation ( ) of 0.5-1.8 nm (20) at 60°C. Turkevich et al (21) replicated Ostwald's protocol and reported the particle size to be 12.0 ± 3.6 nm (μ ± ) based on TEM images.…”

Section: Introductionmentioning

confidence: 99%

Room-temperature synthesis of gold nanoparticles — Size-control by slow addition

2010

View full text Add to dashboard Cite

We report a simple and rapid process for the roomtemperature synthesis of gold nanoparticles using tannic acid, a green reagent, as both the reducing and stabilising agent. We systematically investigated the effect of pH on the size distribution of nanoparticles synthesized. Based on induction time and -potential measurements, we show that particle size distribution is controlled by a fine balance between the rates of reduction (determined by the initial pH of reactants) and coalescence (determined by the pH of the reaction mixture) in the initial period of growth. This insight led to the optimal batch process for size-controlled synthesis of 2-10 nm gold nanoparticles -slow addition (within 10 minutes) of chloroauric acid into tannic acid.

show abstract

Methods for Synthesis of Colloidal Gold

Cited by 115 publications

References 42 publications

Gold Sols as Catalysts for Glycerol Oxidation: The Role of Stabilizer

Gold Sols as Catalysts for Glycerol Oxidation: The Role of Stabilizer

A freeze substitution fixation-based gold enlarging technique for EM studies of endocytosed Nanogold-labeled molecules

Room-temperature synthesis of gold nanoparticles — Size-control by slow addition

Contact Info

Product

Resources

About

Methods for Synthesis of Colloidal Gold

Cited by 115 publications

References 42 publications

Gold Sols as Catalysts for Glycerol Oxidation: The Role of Stabilizer

Gold Sols as Catalysts for Glycerol Oxidation: The Role of Stabilizer

A freeze substitution fixation-based gold enlarging technique for EM studies of endocytosed Nanogold-labeled molecules

Room-temperature synthesis of gold nanoparticles &#x2014; Size-control by slow addition

Contact Info

Product

Resources

About

Room-temperature synthesis of gold nanoparticles — Size-control by slow addition