Title
Ligand Adsorption and Exchange on Pegylated Gold Nanoparticles
Abbreviated Journal Title
J. Phys. Chem. C
Keywords
THIOLATED POLY(ETHYLENE GLYCOL); ENHANCED RAMAN-SPECTROSCOPY; SURFACE-PLASMON RESONANCE; PROTEIN ADSORPTION; SILVER NANOPARTICLES; SINGLE GOLD; QUANTIFICATION; ORGANOTHIOLS; STABILITY; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, ; Multidisciplinary
Abstract
Previous researchers proposed that thiolated poly(ethylene glycol) (PEG-SH) adopts a "mushroom-like" conformation on gold nanoparticles (AuNPs) in water. However, information regarding the size and permeability of the PEG-SH mushroom caps and surface area passivated by the PEG-SH mushroom stems are unavailable. Reported herein is our finding that AuNPs that are covered by saturation packed PEG-SHs all have large fractions of AuNP surface area available for ligand adsorption and exchange. The model ligands adenine and 2-mercaptobenzimidazole (2-MBI) can rapidly penetrate the PEG-SH overlayer and adsorb onto the AuNP surface. Most of the ligand adsorption and exchange occurs within the first minutes of the ligand addition. The fraction of AuNP surface area passivated by saturation packed model PEG-SHs are similar to 25%, similar to 20%, and similar to 9% for PEG-SHs with molecular weights of 2000, 5000, and 30 000 g/mol, respectively. Localized surface plasmonic resonance and dynamic light scattering show that the PEG-SH overlayer is drastically more loosely packed than the protein bovine serum albumin on AuNPs. Studies investigating the effect of aging the AuNP/PEG-SH mixtures on subsequent adenine adsorption onto the pegylated AuNPs revealed that PEG-SHs reach approximately a steady-state binding on AuNPs within 3 h of sample incubation. This work sheds new insights into the kinetics, structures, and conformations of PEG-SHs on AuNPs and demonstrates that pegylated AuNPs can be used as an important platform for studying ligand interaction with AuNPs. In addition, it also opens a new avenue for fabrication of multicomponent functionalized nanoparticles.
Journal Title
Journal of Physical Chemistry C
Volume
118
Issue/Number
20
Publication Date
1-1-2014
Document Type
Article
DOI Link
Language
English
First Page
11111
Last Page
11119
WOS Identifier
ISSN
1932-7447
Recommended Citation
"Ligand Adsorption and Exchange on Pegylated Gold Nanoparticles" (2014). Faculty Bibliography 2010s. 6096.
https://stars.library.ucf.edu/facultybib2010/6096
Comments
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