Molecular assemblers may still be the stuff of science fiction, but manually building microscopic things out of molecules has been the norm for many years. At least, in our own current crude way. Nanoviolins, nano-engines, nano-wheels, you name it.
Then there’s this new research, which, in an attempt to further showcase the future of building things at the nanoscale, recently presented another nano-engineering masterpiece: a mechanically functional, nanoscale ‘monster truck’.
Tread Small, Ride Big
Masson and Saw-Wai Hla, Ph.D, led a team of researchers at Ohio University in order to design and build a car that is 3.5 nanometers in length. To put this to scale, human hair is about 100,000 nanometers wide, and the human DNA is about 2.5 nanometers. In terms of size, this definitely is smaller than you’d ever be able to see in a regular microscope. The amazing part? It is designed to be fully functional, wheels n’ axles and all.
The Bobcat Nanowagon, as it is officially named, used large Cucurbituril (C36H36N24O12) molecules to form the wheels. Its significantly larger size compared to the pseudorotaxane ‘chassis’ made it look like a monster truck, hence its designation. While the nanoscale monster truck’s wheels are completely functional, it does not actually have an engine. It moves via charge repulsion. Simply put, the researchers push the car using two positive sides, one from the car and one from the locomotive instrument (a tunneling microscope).
The tiny monster truck first proved its capabilities during a competition, which was held last April 28th at the French National Center for Scientific Research (CNRS) in Toulouse. Racing along with six other nanoscale cars from other research groups, it ran across a gold plated racetrack in a bid to achieve first place. Unfortunately, after running for about 43 nanometers (and about 30 or so hours), it got stuck, and eventually only won third place.
Nanoscale Machines, Reloaded
The development of Bobcat Nanowagon may not sound amazing, nor important in today’s applied technologies. However, it did prove several possibilities in nanotechnology today and into the near future. Mainly, that despite current development hurdles, molecular machines can now be built far more complex than ever.
Not only did the researchers succeed in building “an intact supramolecular assembly onto a surface and control its motion”, but the data they have collated through this study can be made to better publicize current advancements in nanotechnology. If the public then realizes just how far nanotechnology (at least the molecular assembly part) is now, the development of commercial nanoassembly-based systems might just be a few proposals ahead.
Aside from the initial demonstration objectives, the research has also yielded one more important discovery. They attempted to suspend the nanoscale monster truck’s chassis in water, before adding its wheels and removing the water. They noticed that 70 percent of the time, at least two wheels turned on their sides to form a “hoverboard-like” structure with the chassis.
There are no official explanations for the phenomenon at the time, but research states that it is a “theoretical curiosity”. It was an observation that might just help us better understand the do’s and dont’s of nanoscale assembly in accordance to atomic scale interactions.
Source: American Chemical Society