The effects of polyethylene glycol on the nucleation and growth of DNA-functionalized gold nanoparticles crystals

This study presents findings on the crystal growth of DNA-functionalized gold nanoparticles (DNA-AuNPs) in the presence of polyethylene glycol (PEG), serving as an additive. Utilizing optical microscopy, UV-Vis spectroscopy, dynamic light scattering and small angle x-ray scattering, we observed enhanced crystal nucleation and growth facilitated by PEG. This effect is attributed to PEG's promotion of the overall crystallization process of DNA-AuNPs. Furthermore, we examined the influence of PEG on short-range interactions between DNA-AuNPs, where DNA binding occurs, and long-range interactions in colloidal solutions. The results suggest that PEG plays a crucial role in both promoting crystal nucleation and influencing the interactions between DNA-AuNPs at various distances, shedding light on its potential impact on DNA-AuNP crystal formation.