Gold sol particles

As mentioned in Section 3.1, the pyrolytic carbon XC72R resulted useful for immobilizing gold sol particles owing... 

Creighton J.A., Blatchford C.B., Albrecht M.C., Plasma resonance enhancement of Raman-scattering by pyridine adsorbed on silver or gold sol particles of size comparable to the excitation wavelength, J. Chem. Soc. Faraday Trans. 1979 2 790-798. 

A typical immunoassay format in a flow-through device has an antibody covalently coupled to the surface of a porous matrix. When the patient sample is added to the matrix, the analyte of interest binds to the antibody. Addition of a second labeled antibody forms a sandwich and traps the label at the position of the first antibody. If the label is gold sol particles or colored latex, the label is directly visualized or quantified by reflectance spectrophotometry in a separate reader, Another important feature of this type of technology is the incorporation of a built-in quality monitor that indicates positive if all the reagents have been stored and the device operated correctly. In all these different formats,... 

AP particles are of colloidal size and can be observed under an electron microscope. Figures 10, 11, and 12 show electron micrographs of AP from the solutions. X-ray diffraction work has indicated that this material (the hexagonal platelets) is gibbsite (8, 30). Also shown on the micrographs are gold sol particles (small, dark spheres and tetrahedrons). 

These figures show much of the detail of the particles, such as their typical crystalline shape and imperfections. The gold sol particles as pre-... 

The results presented in Figures 9 and 10 show that, despite the high Brookfield viscosities, the gold sol experienced viscosities close to that of water. It can, therefore, be inferred that the gold sol particles occupied low-viscosity regions in the gel, which, from Bagley s hypothesis, could be viewed as the interstices between the swollen microgel particles. 

Roark D, Yphantis DA (1969) Ann New York Acad Sci 164 245 Rinde H (1928) The Distribuhon of the Sizes of Particles in Gold Sols Prepared According to the Nuclear Method. PhD Thesis, University of Uppsala, Uppsala, Sweden Harding SE (1988) Gums and Stabilisers for the Food Industry 4 15 http //www.wyatt.com/... 

Table 7. Influence of gold sol concentration on particle diameter.

After few minutes of gold sol preparation, metal particles have to be immobilized on a suitable support for practical purpose. Normally this step is simply performed by dipping the support in the sol. The metal particles are... 

As reported in the literature by Heard et al. [156], the colour of the gold sol depended strongly on the size of the particles. The blue sol corresponded to 20-30 nm elongated agglomerated particles whereas pink sols corresponded to <20 nm particle size. 

Graham coined the term "colloid" to describe suspensions of small particles in a liquid.(J ) Such particles are generally considered to be from 1 to 5000 nm in diameter and are not easily precipitated, filtered, or observed by ordinary optical microscopes. The topic of this paper is metallic colloidal particles, often called metal sols, with special emphasis on non-aqueous media. Some history of gold sols is appropriate. 

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