Atomistic Molecular Dynamics Simulation Study on the Interaction between Atomically Precise Thiolate-Protected Gold
1Department of Chemistry, Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Xiangtan University, Xiangtan, Hunan Province 411105, China.
Langmuir : the ACS Journal of Surfaces and Colloids
|January 26, 2022
Summary
Atomically precise gold nanoclusters (Au NCs) interact differently with phospholipid membranes based on size and surface ligands. The Au25(SR)18 cluster showed the highest affinity, with ligand aggregation and charge density impacting membrane interactions.
Area of Science:
- Nanotechnology
- Biophysics
- Computational Chemistry
Background:
- Atomically precise gold nanoclusters (Au NCs) are emerging materials with unique properties.
- Understanding their interaction with biological membranes is crucial for applications in nanomedicine and drug delivery.
- Phospholipid membranes serve as fundamental barriers in biological systems.
Purpose of the Study:
- To investigate the interaction of various gold nanoclusters (Au NCs) with phospholipid membranes.
- To determine how cluster size, ligand type, and surface charge density influence membrane interaction and transmembrane behavior.
- To identify key factors governing the affinity and permeability of Au NCs across membranes.
Main Methods:
- All-atom molecular dynamics (AAMD) simulations were employed to model the interactions.
- Six different atomically accurate gold nanoclusters (Au25(SR)18, Au36(SR)24, Au44(SR)28, Au68(SR)32, Au144(SR)60, and Au314(SR)96) were simulated.
- The effects of cluster size, ligand aggregation, and surface charge density were systematically analyzed.
Main Results:
- Gold nanoclusters exhibited diverse transmembrane behaviors influenced by their size and surface modifications.
- The Au25(SR)18 cluster demonstrated the highest affinity for phospholipid membranes among the studied clusters.
- Ligand aggregation mode and surface charge density were identified as critical factors affecting Au NC-membrane interactions.
- A balanced ratio of hydrophilic and hydrophobic ligands enhanced Au NC permeability.
Conclusions:
- The interaction of gold nanoclusters with phospholipid membranes is highly dependent on their structural and surface properties.
- Au25(SR)18 is a promising candidate for membrane interaction studies due to its high affinity.
- Surface ligand characteristics, including aggregation and hydrophilicity/hydrophobicity balance, are key determinants of Au NCs' membrane permeability and utility in biological applications.
