Using catalytic AFM probes for nanoscale chemical patterning at surfaces

For those with an interest in scanning probe lithography methods, work has recently been reported in Chemical Science (RSC Publishing) by a researchers from Aix Marseille University into the use of an atomic force microscope equipped with a modified probe, to locally catalyse reactions at a functionalised surface.

Commercial AFM probes were modified with a homogenous catalyst (1,4,7-triazacyclononane manganese complex) and subsequently used to promote epoxidation of an alkene-terminated self-assembled monolayer on silicon, in the presence of H₂O₂ (oxidant), at spatially defined surface regions, i.e. patterned regions, bearing epoxide functionality within a alkene monolayer, are produced.  

Furthermore, the resulting epoxides formed within the monolayer were demonstrated to be able to act as anchoring sites for covalently grafting other molecules to the monolayer surface, here via a ring opening reaction of the epoxide with N-octylpiperazine. This strategy opens up the possibility for the attaching a variety of molecules (e.g. peptides, proteins/enzymes) at spatially defined regions upon a surface.



Source: Chemical Science | Chemistry World | RSC Publishing

The authors anticipate that the principles behind this AFM chemical lithography method can be extended to numerous other metal-catalysed reactions, meaning the technique could offer a viable route for carrying out a host of different organic reactions locally on a surface for the creation complex two-dimensional chemical patterns.

http://www.rsc.org/chemistryworld/2013/06/nanoscale-surface-design-homogeneous-catalysis-epoxidation

For those with a subscription to Chemical Science (RSC Publishing), the publication can be found at:
http://pubs.rsc.org/en/Content/ArticleLanding/2013/SC/c3sc50979f