Protein nanostructures formed via direct-write dip-pen nanolithography.

We report a tip modification strategy coupled with dip-pen nanolithography for depositing proteins on a surface. This methodology offers patterning capabilities on the scale of 45 nm to many micrometers length. The biorecognition properties of nanofeatures composed of immunoglobulin-gamma (IgG) were confirmed by reacting the array with gold nanoparticles coated with anti-IgG. Furthermore, a two component nanoarray was fabricated in direct-write fashion by DPN, and the biorecognition properties of this structure were investigated by AFM without biodiagnostic labels.