Investigating the impact of positively charged gold nanoparticle (AuNP) concentration in water/Cl− solutions using molecular dynamics simulations

Abstract

This study presents a detailed analysis of the interactions between positively charged gold nanoparticles Au144(SRNH3+)60 and chloride ions (Cl−) in aqueous solution, using molecular dynamics simulations. Four systems with varying amounts of chloride ions were investigated: 60 Cl−, 120 Cl−, 180 Cl−, and 240 Cl−, alongside varying quantities of nanoparticles. The focus of this research is to elucidate the energies involved, hydrogen bonding patterns, and radial distribution of ions around the gold nanoparticles, providing a fundamental basis for evaluating the potential applications of these systems in disease treatment. The results reveal significant differences in the Coulomb and van der Waals interaction energies between nanoparticles and ions, as well as between nanoparticles and water molecules. Furthermore, this study highlights the patterns and lifetimes of hydrogen bonds between nanoparticles and water molecules, along with the mobility of system components in solution. These findings have important implications for potential applications in bionanotechnology, offering a deeper understanding of the interactions between ions and gold-based nanoparticles.