The preparation of a family of composite particles comprising gold nanoparticles (AuNP) assembled at a polystyrene (PS) surface is reported. Tunable loading is demonstrated for AuNP sizes (4.5-26 nm). The robust composites are stable to multiple centrifugation and dispersion cycles and to conditions of high ionic strength, physiological buffer and cell culture media. These properties provide potential for a variety of applications from cellular studies to catalysis.