Nanocontact printing: A route to sub-50-nm-scale chemical and biological patterning

This paper describes the first example of the patterning of surfaces via nanocontact printing with chemically distinct features in the <50 nm scale over 3 x 3 mm(2). These ultrasmall features are achieved via a combination of "sharp" and "hard" poly(dimethylsiloxane) stamps, keeping the contact area in the 50 nm domain, and high molecular weight inks to avoid diffusion. The patterns consist of dendrimers or proteins and can be used as a scaffold for further modification with gold nanoparticles.