Interactions between suspended nanowires and patterned surfaces

Gold nanowires, 350 nm in diameter and 3-6 mum in length, were derivatized by using positively and negatively charged self-assembled monolayers. The interactions between these particles and surfaces were investigated as a function of their surface chemistry and topography. Electrostatically, repulsive sulfonate-sulfonate interactions resulted in mobile particles on the surface, whereas electrostatically attractive interactions between polyamines and sulfonates immobilized the particles. Patterned surfaces were selectively derivatized with particles using,these attractive and repulsive interactions. By lithographically defining surface wells that were commensurate with the length of the nanowires, nanowire bundles were assembled in the wells.