Dopamine Functionalized Polyethylene Glycol for Improving Stability of Gold Nanoparticles against Reactive Oxygen Species in Serum.

PEGylation is the most effective antifouling method for the surface modification of gold nanoparticles (AuNPs). However, thiol-terminated polyethylene glycol (PEG) ligands tethered on the AuNPs are instable in serum and can detach from the AuNP surface, resulting in a significant reduce of their antifouling properties. Herein, it is reported that reactive oxygen species (ROS) is a major factor causing the detachment of PEG ligands from AuNP surfaces.