Multiscale Molecular Dynamics Simulation of Multiple Protein Adsorption on Gold Nanoparticles

Area of Science:

• Biophysics
• Materials Science
• Computational Chemistry

Background:

• Protein adsorption onto nanomaterials, particularly gold nanoparticles (AuNPs), is crucial for understanding biological interactions and developing nanomedicine.
• The formation of a protein corona, a layer of proteins adsorbed onto nanoparticles, significantly influences nanoparticle behavior in biological environments.
• Experimental data on protein adsorption to AuNPs is often controversial, necessitating detailed theoretical investigations.

Purpose of the Study:

• To elucidate the adsorption mechanisms of hemoglobin, myoglobin, and trypsin onto citrate-capped 15 nm AuNPs using multiscale molecular dynamics simulations.
• To investigate the determinants of single protein adsorption and the simultaneous adsorption of multiple proteins.
• To provide molecular-level insights into the protein corona formation process on AuNPs.

Main Methods:

• Multiscale molecular dynamics simulations, including Coarse-Grained (CG) and Meso-Scale (MS) approaches.
• Simulation of individual protein adsorption and competitive adsorption of three distinct proteins (hemoglobin, myoglobin, trypsin).
• Analysis of protein-nanoparticle interactions, binding sites, and structural changes.

Main Results:

• Detailed description of the protein recognition and adsorption process onto AuNPs.
• Quantification of proteins involved in early-stage protein corona formation.
• Identification of protein competition dynamics for AuNP surface binding.
• Characterization of interaction modalities between AuNPs and specific protein binding sites.
• Assessment of protein structural preservation and alteration upon adsorption.

Conclusions:

• The study provides a comprehensive molecular-level understanding of protein adsorption on AuNPs, reconciling controversial experimental findings.
• Simulation results offer critical insights into the complex processes governing protein corona formation and its impact on protein structure.
• This work lays the foundation for designing nanomaterials with controlled protein interactions for biomedical applications.