Expeditious synthesis of water-soluble, monolayer-protected gold nanoparticles of controlled size and monolayer composition.
A protocol is reported for the preparation of water-soluble, thiol-protected Au nanoparticles (Au-MPC) where dioctylamine is used as a stabilizing agent when the gold cluster is formed using the two-phase Brust and Schiffrin procedure. The amount of amine controls the size of the nanoparticles in the 1.9-8.9 nm diameter range. The final stabilization of the gold clusters by addition of functionalized thiols is performed under very mild conditions compatible with most biomolecules. The procedure is suitable for a wide variety of functional groups present in the thiol and allows one to use thiol mixtures with a precise control of their composition in the monolayer. As a proof of principle, examples of nanoparticles protected with thiols comprising functional groups ranging from polyethers, saccharides, polyamines and ammonium ions are reported.
Manea
Flavio
F
Department of Chemical Sciences and ITM-CNR, University of Padova, Padova Section, 35131 Padua, Italy.
Bindoli
Cristiano
C
Polizzi
Stefano
S
Lay
Luigi
L
Scrimin
Paolo
P