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Updated: Jun 12, 2026
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Insights into the Interactions of Amino Acids and Peptides with Inorganic Materials Using Single-Molecule Force Spectroscopy
Published on: March 6, 2017
Exploring the surface charge on peptide-gold nanoparticle conjugates by force spectroscopy
Ariel R Guerrero1, Leonardo Caballero, Alberto Adeva
1Materials and Surface Science Group, University of Windsor, 401 Sunset Avenue, Windsor, Ontario N9B 3P4, Canada.
Langmuir : the ACS Journal of Surfaces and Colloids
|June 19, 2010
Summary
Peptide sequence influences charge exposure on gold nanoparticle conjugates, impacting their use in Alzheimer's disease diagnostics and therapy. Understanding these interactions is key for developing effective biomedical applications.
Area of Science:
- Nanotechnology
- Biomaterials Science
- Biochemistry
Background:
- Conformation and charge of peptides on gold nanoparticles (AuNPs) are crucial for colloidal stability and biological target recognition.
- Peptide-AuNP conjugates have potential in diagnostics and therapy, particularly for Alzheimer's disease by targeting amyloid beta (Abeta) aggregates.
Purpose of the Study:
- To investigate how peptide sequence affects the charge exposure and conformation of peptides attached to AuNPs.
- To compare the surface charge density and charge per molecule of three different peptide isomers conjugated to AuNPs.
- To understand the acid-base behavior of surface-anchored peptides.
Main Methods:
- Preparation of AuNP conjugates with three isomer peptides (i0, i1, i2) designed to recognize Abeta.
- Force spectroscopy measurements on peptide-AuNP conjugates immobilized on glass surfaces.
- Analysis of interactions between peptide-functionalized tips and the immobilized conjugates.
Main Results:
- Isomers i0 and i2 showed higher surface charge density due to greater functionalization compared to i1.
- Isomer i1 exhibited a higher charge per peptide molecule, potentially due to its local conformation on the AuNP surface.
- The acid-base behavior of anchored peptides differed from free peptides, possibly due to limited accessibility of the N-terminal group.
Conclusions:
- Peptide sequence significantly impacts the surface charge characteristics of AuNP conjugates.
- Conformational changes and accessibility of functional groups influence peptide behavior on AuNP surfaces.
- Surface immobilization enables detailed characterization of local charge exposure for peptide-AuNP systems across various pH levels.
