Short Report on the International Workshop
DNA-Based Nanotechnology: Digital Chemistry (DNATEC14)
at the Max Planck Institute for the Physics of Complex Systems, Dresden
May 5th - May 9th, 2014

Building intricate functional nanoscale structures is one of the most important challenges for science and technology. Top-down methods, such as lithography, are being pushed to their limits in today's manufacturing processes, making it ever more important to develop bottom-up methods that produce structure well beyond the traditional scale of molecules. Among the bottom-up methods, DNA nanotechnology stands out as the most rapidly growing, and perhaps most promising field. Due to the programmability of DNA duplexes, their well-defined geometry, their mechanical properties, and the ability to combine duplexes with branching elements, such as Holliday junctions or turns, a structural diversity is achievable that is unrivalled by other techniques. At the same time, the ready availability of synthetic oligonucleotides and long single-stranded templates has opened the door to the fabrication of structures up to several hundred nanometers in size with predictable location of every single atom in the mega-Dalton arrangement. While single-stranded DNA tile assembly has been known for more than two decades, DNA origami constitutes a more recent development.

The workshop was the second of its kind in Dresden. While the first DNATEC meeting, in 2009, had focused on new structures, this year's conference was focused on function. One hot topic that appeared in numerous presentations was nanophotonics. The ability to place colloidal nanoparticles on DNA scaffolds opened the door to forays into structures acting as antennae at optical wavelengths, materials with negative refractive index, or opto-electronic circuits. Another topic that was hotly debated was dynamic systems. Results presented ranged from controlled oscillating or evolving systems to nanorobots. In some instances, the motion of DNA walker-assemblies or of enzymatic machinery on DNA origami tracks can now be observed in real time, using fast-scan atomic force microscopy, as presented in a very impressive way by Hiroshi Sugiyama from Kyoto University. Anyone proposing ten years ago that individual functional molecules would be observed spectroscopically in real time and in their programmed movement along a surface would have met with scepticism. Today, this is a reality. Yet another area in which great progress has been made is the interfacing of artificial DNA structures and living cells. Several talks showed, how the field of synthetic biology is beginning to merge with DNA nanotechnology to produce biomimetic cell assemblies with new properties. Protocells can be designed, their membranes modelled through structural DNA origami, and their porosity tunes by artificial nanopores. Few fields can boast such an impressive synergy between physics, chemistry, and biology. Only the collaboration between these fields then produces the technological advances that were proudly displayed at the meeting.

It would be near impossible, if not unfair, to single out individual contributors to this meeting. It is noteworthy, though, that the participants included Nadrian Seeman, who pioneered the field of DNA nanotechnology in the 1980s, and most of the leaders of the field as it is perceived today. Speakers hailed from all parts of the scientific world, including the East and the West Coast of the USA, Japan, India, the UK and many other European countries. In addition, the meeting attracted many young researchers, working in the field of DNA nanotechnology today. The presentation format left time for in-depth discussions that were supplemented by the poster sessions and the countless exchanges during breaks and meals. The Max Planck Institute for the Physics of Complex Systems provided a perfect setting for a truly interdisciplinary conference on a fast developing topic that has moved from a curiosity to a structuring technique to an avant-garde method for assembling functional machines. Plans for the next DNATEC meeting are already being talked about!