LAUSR

PEGylation is the most effective antifouling method for the surface modification of gold nanoparticles (AuNPs). However, thiol-terminated polyethylene glycol (HS-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, we report that reactive oxygen species (ROS) is a major factor causing the detachment of PEG ligands from AuNP surfaces. By covalently backfilling dopamine-functionalized PEG on the AuNPs, the stability of PEG ligands on AuNP surface and the antifouling ability of AuNPs can be effectively improved. Tuning the balance between ROS and dopamine-functionalized PEG can be used as a new strategy to control the self-assembly of AuNPs and serum proteins. This article is protected by copyright. All rights reserved.