Metal and Si-based nanostructures have drawn increasing interest due to their potential uses in catalysis, biological sensors, and nanoelectronics among others. Therefore, in the present work, several nanostructures were produced, characterized and tested. In particular, the conventional synthesis of noble-metal nanostructures through the polyol method was modified by replacing poly-vinyl pyrrolidone PVP with poly-diallyl dimethyl ammonium chloride PDDA. As PDDA is a cationic polyelectrolyte, the initial strong electrostatic interaction between PDDA and the anionic metal precursors produce the formation of stable ion pairs, so the reactivity of the different species can be tailored and particles with different internal structure, i.e. crystallinity, can be produced.