Unique grafting of the poly(glycidyl methacrylate) from the surface of graphene oxide (GO) with the controllable reduction of GO particles was performed in a single-step reaction using atom transfer radical polymerization technique. The control of the GO surface reduction and modification can be achieved by appropriate selection of the ratio between tertiary amine and GO particle contents. Finely tuned electrical conductivity of the GO-PGMA particles enables simple tailoring of electro-responsive properties of their silicone oil suspensions. (C) 2015 Elsevier B.V. All rights reserved.