Effects of Ligand Composition on Protein Corona Formation around, and the Surface Structure of, Au Nanoparticles

Coatings on nanoparticles in biological environments greatly impact the dynamics and stability of the nanoparticles. Destinations, and potential function of nanoparticles can be changed by attaching ligands to the nanoparticle surface. In this study, molecular dynamics is used to study how different ligands, and specifically different chemical end groups, alter the surface structure and dynamics of the ligands in solution. PEG2000, Alkyl-PEG600-Glucosamide, and Alkyl-PEG600-Butanamide and their specific interactions with Bovine Serum Albumin and Concanavalin A are studied in detail. The effects of altering the end group on Alkyl-PEG600-Butanamide to Propanamide and Ethanamide are explored, and is found to have a significant impact on the surface structure at the ligand-water interface, potentially altering nanoparticle interactions in solution, as well as protein corona formation. The CHARMM36-Interface force field is used throughout all simulations which yields interfacial properties directly comparable to experimental measurements. The study is expected to lead to new insight into how protein-ligand interactions work, as well as advancing understanding of how ligand conformations can affect their environmental interactions.