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Updated: Apr 5, 2026
10:09
Synthesis and Characterization of Amphiphilic Gold Nanoparticles
Published on: July 2, 2019
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Probing the Structure, Composition, and Spatial Distribution of Ligands on Gold Nanorods
Michael J A Hore1,2, Xingchen Ye, Jamie Ford
1National Institute of Standards and Technology , Center for Neutron Research, 100 Bureau Drive, Gaithersburg, Maryland 20899, United States.
Nano Letters
|August 21, 2015
Summary
Small-angle neutron scattering (SANS) reveals the structure of surface layers on gold nanorods. This technique quantifies surfactant and polymer coatings, crucial for applications in medicine and materials science.
Area of Science:
- Nanotechnology
- Materials Science
- Biomedical Engineering
Background:
- Gold nanorods (Au NRs) functionalization with surface ligands is critical for their application in diverse fields.
- Understanding the structure and composition of these surface layers is essential for optimizing nanoparticle performance.
Purpose of the Study:
- To quantitatively determine the location, structure, and composition of surfactant and poly(ethylene glycol) (PEG) layers on gold nanorods using SANS.
- To investigate the retention of surfactants from seed crystals to the final Au NR product.
- To analyze the intactness of the surfactant bilayer during PEGylation.
Main Methods:
- Small-angle neutron scattering (SANS) measurements on surfactant- or PEG-coated gold nanorods in solution.
- Synthesis of gold nanorods using seed crystals coated with deuterated cetyltrimethylammonium bromide (dCTAB).
- Mass spectrometry for detecting surfactant and PEG presence.
Main Results:
- SANS quantitatively characterized the structure and composition of surface layers on gold nanorods.
- Exploiting isotopic sensitivity of SANS, minimal exchange of deuterated surfactant from seed crystals to final product was observed.
- PEGylation of Au NRs did not disrupt the underlying surfactant bilayer; SANS indicated predominantly surfactant composition despite mass spectrometry detecting both surfactant and PEG.
Conclusions:
- SANS provides quantitative insights into the structure of grafted polymer and surfactant layers on gold nanorod surfaces.
- Findings advance the understanding of gold nanorod synthesis and functionalization.
- Results have implications for the fabrication of advanced plasmonic and biomedical materials.
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