Are nanobots on their way?

US researchers have built a proto-prototype nano assembler

The first real steps towards building a microscopic device that can construct nano machines have been taken by US researchers. Writing in the peer-reviewed publication, International Journal of Nanomanufacturing from Inderscience Publishers, researchers describe an early prototype for a nanoassembler.

In his 1986 book, The Engines of Creation, K Eric Drexler set down the long-term aim of nanotechnology - to create an assembler, a microscopic device, a robot, that could construct yet smaller devices from individual atoms and molecules.

For the last two decades, those researchers who recognized the potential have taken diminutive steps towards such a nanoassembler. Those taking the top-down approach have seen the manipulative power of the atomic force microscope (AFM), a machine that can observe and handle single atoms, as one solution. Those taking the bottom-up approach are using chemistry to build molecular machinery.

However, neither the top-down nor the bottom-up approach is yet to fulfill Drexler's prophecy of functional nanobots that can construct other machines on a scale of just a few billionths of a meter.

Jason Gorman of the Intelligent Systems Division at the US government's National Institute of Standards and Technology (NIST) concedes that, "Nanoassembly is extremely challenging." Yet the rewards could be enormous with the ultimate potential of creating a technology that can construct almost any material from atoms and molecules from super-strong but incredibly lightweight construction materials to a molecular computer or even nanobots that can make other nanobots to solve global problems, such as food, water, and energy shortages.

Gorman and his colleagues at NIST have taken a novel approach to building a nanoassembler and reveal details in a forthcoming issue of the International Journal of Nanomanufacturing. "Our demonstration is still a work in progress," says Gorman, "you might describe it as a 'proto-prototype' for a nanoassembler."

AFM is the most commonly employed approach for top-down nanomanipulation research, explains Gorman. However, AFM suffers from a number limitations, as the nanoparticles stick together during manipulation and cannot be lifted from the substrate. This means that nanodevices constructed using AFM may be aesthetically pleasing and provide insights into what might be achievable but it cannot build practical nano machines.