Assembly of Nanoparticles using Surface‐Grafted Orthogonal Polymer Gradients

Summary: We report on preparing poly(2‐(dimethylamino)ethyl methacrylate) (PDMAEMA) gradient substrate, wherein molecular weight (MW) and grafting density ( σ ) of the surface‐anchored PDMAEMA chains vary continuously in two orthogonal directions. Such a specimen is used to control the assembly of charged gold nanoparticles. Increasing MW and σ of the grafted PDMAEMA cause an enhanced binding of the nanoparticles to PDMAEMA, thus leading to an orthogonal number density gradient of surface‐bound gold nanoparticles. magnified image