Journal
ACS NANO
Volume 5, Issue 6, Pages 4570-4580Publisher
AMER CHEMICAL SOC
DOI: 10.1021/nn200276a
Keywords
gold nanoparticles; self-assembled monolayers; thioctic acid; nanoparticle stability
Categories
Funding
- Roy J. Carver Charitable Trust
- NIH-NCRR, University of Iowa [1UL1RR024979, 1KL2RR024980, 1TL1RR024981]
Ask authors/readers for more resources
Self-assembled monolayer (SAM) modification is a widely used method to improve the functionality and stability of bulk and nanoscale materials. For Instance, the chemical compatibility and utility of solution-phase nanoparticles are often improved using covalently bound SAMs. Herein, solution-phase gold nanoparticles are modified with thioctic acid SAMs in the presence and absence of salt. Molecular packing density on the nanoparticle surfaces is estimated using X-ray photoelectron spectroscopy and increases by 20% when molecular self-assembly occurs in the presence versus the absence of salt. We hypothesize that as the ionic strength of the solution Increases, pinhole and collapsed-site defects in the SAM are more easily accessible as the electrostatic interaction energy between adjacent molecules decreases, thereby facilitating the subsequent assembly of additional thioctic acid molecules. Significantly, increased SAM packing densities Increase the stability of functionalized gold nanoparticles by a factor of 2 relative to nanoparticles functionalized in the absence of salt. These results are expected to improve the reproducible functionalization of solution-phase nanomaterials for various applications.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available