shown earlier that when a completely cured PDMS surface, e.g. one cured at 80 o C for 5 hours, is brought in contact with the salt solution, the reaction occurs at a slow rate because of depleted concentration of SiH moieties at the PDMS surface; consequently, the nanoparticles continue to evolve there for days and weeks. However, in our experiment, the PDMS films were crosslinked at room temperature for 72 hours, thereby ensuring presence of excess SiH at the channel surface. Considering that the surface concentration of the SiH moieties,