Single particle studies of the autocatalytic metal deposition onto surface-bound gold nanoparticles reveal a linear growth

Specific metal deposition on nanoparticles is of outstanding importance in molecular construction as well as for signal enhancement in bioanalytics. To characterize the growth mechanism we studied the enhancement process of immobilized gold nanoparticle ensembles at single particle level by atomic force microscopy, monitoring the very same particle arrangements after each enhancement step. The particles grew linearly and a dependence of the growth rate on the seed diameter was found. The findings may help us to understand the underlying growth mechanism.