Regioselective functionalization of dimpled silica particles

Abstract

Multipod-like particles made of a silica core surrounded by polystyrene nodules have been used as precursors to synthesize silica particles with 3 or 12 dimples through the selective growth of the dielectric core. Using the polymer nodules as temporary protecting masks, we regioselectively grafted amino groups onto the unprotected silica surface, as revealed by the adsorption of gold markers. After dissolution of the PS nodules, some polymer chains remained grafted onto the silica surface, forming organic bumps at the bottom of the dimples. These residues were also selectively functionalized, leading to silica particles with both entropic and enthalpic patches.