Engineering Nucleobase-Functionalized Bottlebrush Polymers as Multivalent Ligands for the Surface Protection of Colloidal Nanomaterials

Nucleic acids have long been recognized for their essential role in storing and transmitting genetic information. Inspired by the functional and recognition properties of DNA and RNA, we designed a class of nucleobase-appended bottlebrush polymers to serve as advanced surface ligands for stabilizing plasmonic nanomaterials. Leveraging multivalent metal–nucleobase interactions, these bottlebrush polymers provided robust protection to colloidal nanomaterials, preventing undesired aggregation under harsh conditions including high salt concentrations, broad pH ranges, freeze–thaw cycles, and elevated temperatures. Additionally, the surface attachment of polymer ligands enabled the phase transfer of nanoparticles from aqueous media to organic media. The customizable design of these polymeric ligands facilitates the further functionalization of ligand-protected nanoparticles. Compared to conventional thiol-based ligands, the nucleobase-functionalized bottlebrush ligands exhibited a superior ability to offer colloidal stability under harsh conditions, owing to their multivalent interactions. This unique stability will open opportunities for the development of advanced biosensing, imaging, and therapeutic applications.