A team from Belgium, Italy, and France has achieved inspiring nanotech results in bonding single molecules to a surface using an AFM (atomic force microscope). From Nature Nanotechnology, which — as of today at least — is kindly giving free access to the full text of the article:
Mechanochemistry: targeted delivery of single molecules
The use of scanning probe microscopy-based techniques to manipulate single molecules and deliver them in a precisely controlled manner to a specific target represents a significant nanotechnological challenge. The ultimate physical limit in the design and fabrication of organic surfaces can be reached using this approach. Here we show that the atomic force microscope (AFM), which has been used extensively to investigate the stretching of individual molecules, can deliver and immobilize single molecules, one at a time, on a surface. Reactive polymer molecules, attached at one end to an AFM tip, are brought into contact with a modified silicon substrate to which they become linked by a chemical reaction. When the AFM tip is pulled away from the surface, the resulting mechanical force causes the weakest bond — the one between the tip and polymer — to break. This process transfers the polymer molecule to the substrate where it can be modified by further chemical reactions…
The present experiments not only show that we can deliver single molecules onto the substrate and covalently immobilize them, but also that these molecules can be subsequently modified by further chemical reactions…By playing with the nature of the (co)polymer grafted to the tip and the nature of the substrate, high-resolution patterns of chemical functionalities on a range of addressable surfaces could be generated. In view of the increasing demand for nano-engineering operations in ‘bottom-up’ nanotechnology, this method provides a tool that operates at the ultimate limits of fabrication of organic surfaces, the single molecule. [emphasis added]
Sacre bleu! Will Europe continue to pull ahead? Let’s see some competition here. —Christine