Straightforward synthesis of gold nanoparticles by adding water to an engineered small dendrimer.

Sébastien Gottis,Anne-Marie Caminade,Régis Laurent,Vincent Collière

doi:10.3762/bjnano.11.95

Abstract

A small water-soluble phosphorus-containing dendrimer was engineered for the complexation of gold(I) and for its reduction under mild conditions. Gold nanoparticles were obtained as colloidal suspensions simply and only when the powdered form of this dendrimer was dissolved in water, as shown by transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDX) analyses. The dendrimers acted simultaneously as mild reducers and as nanoreactors, favoring the self-assembly of gold atoms and promoting the growth and stabilization of isolated gold nanoparticles. Thus, an unprecedented method for the synthesis of colloidal suspensions of water-soluble gold nanoparticles was proposed in this work.

Highlights

Research on nanoparticles (NPs) in general, and gold nanoparticles in particular, results in the generation of thousands of publications every year, including reviews [1,2]
Gold nanoparticles were obtained as colloidal suspensions and only when the powdered form of this dendrimer was dissolved in water, as shown by transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDX) analyses
The synthesis was performed via the Staudinger reaction between 1,6-bis(diphenylphosphino)hexane and a phosphorus azide functionalized by two aldehydes, as previously published [37]

Summary

Introduction

Research on nanoparticles (NPs) in general, and gold nanoparticles in particular, results in the generation of thousands of publications every year, including reviews [1,2]. Different applications for gold nanoparticles have been proposed, for example, in catalysis [3,4] and in biology [5] – especially for bioimaging and cancer therapy [6,7]. The synthesis of gold nanoparticles is carried out by the reaction between HAuCl4 and a reducing agent (in particular NaBH4) in the presence of a suitable compound to simultaneously prevent the aggregation of the nanoparticles and to stabilize them [8,9]. AuCl(tht) (tht = tetrahydrothiophene) has been shown to be an interesting precursor of gold nanoparticles, but only in a few cases [10].

Results

Discussion

Conclusion