la5029542_si_001.pdf (375.32 kB)
Citrate-Stabilized Gold Nanorods
journal contribution
posted on 2015-12-17, 06:00 authored by Jonathan
G. Mehtala, Dmitry Y. Zemlyanov, Joann P. Max, Naveen Kadasala, Shou Zhao, Alexander WeiStable
aqueous dispersions of citrate-stabilized gold nanorods
(cit-GNRs) have been prepared in scalable fashion by surfactant exchange
from cetyltrimethylammonium bromide (CTAB)-stabilized GNRs, using
polystyrenesulfonate (PSS) as a detergent. The surfactant exchange
process was monitored by infrared spectroscopy, surface-enhanced Raman
scattering (SERS), and X-ray photoelectron spectroscopy (XPS). The
latter established the quantitative
displacement of CTAB (by PSS) and of PSS (by citrate). The Cit-GNRs
are indefinitely stable at low ionic strength, and are conducive to
further ligand exchange without loss of dispersion stability. The
reliability of the surface exchange process supports the systematic
analysis of ligand structure on the hydrodynamic size of GNRs, as
described in a companion paper.