Gold nanoparticles procedure

In order to regulate the size of gold nanoparticles, equimolar amount of primary, secondary, or tertiary alkylamines [CnNH2, (Cn)2NH, or (Cn)3N] is added to the controlled thermolysis procedure of... 

Figure 4. Preparative procedure of alkene thiol-stabilized gold nanoparticles. 50% of hexenethiol bounded to the particle surface is hydrogenated to hexanethiol [11b].

C5 - and Cll -stabilized gold nanoparticles were prepared by the same procedure, that is, reducing AUCI4 in the presence of the corresponding ot, co-alkenethiols by NaBH4 (Figure 4). 

Gold nanoparticles were synthesized according to the literature procedure. Fifteen-nanometer Au nanoparticles were made and used for SiNW production. 

Considerable research effort was focused on systems of colloidal gold of which a broad variety of synthetic procedures were reported [140 b, fj. While native colloidal gold solutions are only stable for a restricted time, Brust et al. [141] were able to overcome this problem by developing a simple method for the in situ preparation of alkyl thiol-stabihzed gold nanoparticles. This synthetic route yields air-stable and easy to handle passivated nanoparticles of moderate polydispersity, and is now commonly employed for the preparation of inorganic-organic core-shell composites. Such composites are used as catalytic systems with principally two different functions of the protective 3D-SAM layer. Either the metal nanoparticle core can be used as the catalytically active center and the thiol layer is only used to stabihze the system [142], or the 3D-SAM is used as a Hnker system to chemically attach further catalytic functions [143]. 

An improved synthesis of this type of phosphine-stabilized gold nanoparticle was necessary to make them convenient for use as synthetic intermediates in materials applications. We developed a safer, more convenient, and more versatile synthesis of phosphine-stabilized nanoparticles analogous to those originally reported by Schmid. The synthesis described here eliminates the use of diborane and can be carried out quickly with minimal concern for inert conditions. The nanoparticle product is comparable to that prepared by the Schmid procedure, possessing a core diameter of 1.5 0.4 nm and the same reactivity. In addition, the new synthesis can be adapted to permit the use of a variety of phosphines as passivating ligands and provide control over particle core size. ... 

Recent research involved embedding gold nanoparticles into an MIP layer [82], This procedure enormously increased sensitivity of the method and, therefore, made it suitable for determination of a low molecular weight analyte, such as dopamine. The method was based on the swelling of the MIP gel upon template binding. This swelling resulted in the increase of the distance between the... 

The nucleic acid target immobilization on those nanoparticles depends on particle composition. Immobilization of thiolated DNA on gold nanoparticles via chemisorption is usually preferred since it generates a relatively stable and orientated linkage through a relatively simple procedure (Fig. 9A). 

Fig. 11.9 A representative immunoassay scheme using SERS. (a) A general concept scheme. SERS probe is composed of SERS substrate, reporter molecule, and antibody-conjugate, and (b) An example of immunoassay procedure by Porter et al. [62]. This configuration uses plasmonic coupling between gold nanoparticles and gold film to enhance probe signal...

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