Related Experiment Video
Updated: Jul 19, 2026
14:18
Synthesis, Assembly, and Characterization of Monolayer Protected Gold Nanoparticle Films for Protein Monolayer Electrochemistry
Published on: October 4, 2011
Gold nanoclusters protected by conformationally constrained peptides.
Laura Fabris1, Sabrina Antonello, Lidia Armelao
1Department of Chemistry, University of Padua, via Marzolo 1, 35131 Padua, Italy.
Journal of the American Chemical Society
|January 5, 2006
Summary
Researchers created gold nanoclusters using peptides with alpha-aminoisobutyric acid (Aib). These peptide-protected gold nanoclusters (MPCs) maintain chemical integrity and exhibit unique hydrogen bonding in their monolayer structure.
Area of Science:
- Nanotechnology
- Supramolecular Chemistry
- Peptide Chemistry
Background:
- Alpha-aminoisobutyric acid (Aib) peptides can form stable 3(10)-helical structures stabilized by intramolecular hydrogen bonds.
- Monolayer-protected clusters (MPCs) offer a platform for functionalizing nanomaterials with peptides.
- Controlling peptide structure and its influence on gold nanocluster properties is an active research area.
Purpose of the Study:
- To synthesize and characterize gold nanoclusters protected by thiolated peptides based on the alpha-aminoisobutyric acid (Aib) unit.
- To investigate the role of peptide secondary structure, specifically intramolecular hydrogen bonding, in the formation and properties of gold nanoclusters.
- To compare the ligand density and chemical integrity of peptide-protected gold nanoclusters with those protected by traditional alkanethiolates.
Main Methods:
- Modified two-phase Brust-Schiffrin synthesis for gold nanocluster preparation.
- Comprehensive characterization using (1)H NMR, IR, UV-vis spectroscopy, TEM, TGA, and XPS.
- Analysis of peptide secondary structure and hydrogen bonding within the nanocluster monolayer.
Main Results:
- Successfully prepared gold nanoclusters (MPCs) with core diameters ranging from 1.1-2.3 nm.
- Demonstrated that structured peptides, designed with specific hydrogen bonding capabilities, lead to smaller cluster formation.
- Determined the average formula of the smallest cluster as Au(38)Pep(18) and found peptide ligand density to be 75-85% of that for alkanethiolate MPCs.
- Confirmed the chemical integrity of the peptides upon monolayer formation and identified intra- and interligand hydrogen bonding in the monolayer.
Conclusions:
- Peptide structure significantly influences gold nanocluster size and formation.
- The synthesized gold nanoclusters maintain the chemical integrity of the peptide ligands.
- Peptide ligands in the monolayer exhibit both intra- and interligand hydrogen bonding, contributing to the stability and properties of the nanoclusters.
