Polyelectrolyte-mediated non-micellar synthesis of monodispersed ‘aggregates’ of gold nanoparticles using a microwave approach

‘Aggregates’ of monodispersed gold nanoparticles were synthesized for the first time in large quantities. Those particles were made in presence or in absence of gold seed in a polyelectrolyte solution using microwave heating for about 30–60 s. The average diameters of the particles calculated from TEM and SEM analysis were 22 ± 2 nm. Our analysis found that the polyelectrolyte acted as a reducing as well as a stabilizing agent. It controlled the growth of particles by aligning them on the polymeric chain and the nanoparticles were subsequently self-assembled to form an ‘aggregate’ structure. The synthetic procedure is very fast and the particles are stable for at least 6 months under ambient conditions.