Meet the nano-spiders: The DNA robots that could one day be walking through your body

By Daily Mail Reporters
Last updated at 4:49 PM on 13th May 2010

Scientists have created microscopic robots out of DNA molecules that can walk, turn and even create tiny products of their own on a nano-scale assembly line.
科學家們已從DNA 分子創造出顯微機器人,它可以步行,轉身和甚至創造它們自己的微小產品,在一條納米級的集成線。
The ground-breaking devices outlined in the journal Nature, could one day lead to armies of surgeon robots that could clean human arteries or build computer components.
In one of the projects a team from New York's Columbia University created a spider bot just four nanometres across. This is about 100,000 times smaller than the diameter of a human hair.
在其中一個計劃,從紐約哥倫比亞大學的隊伍創造了一個只有4納米寬的蜘蛛機器人,這是大約 十萬倍的直徑小於人髮。

Robots of the future could operate at the nano-scale level, cleaning arteries or building computer components

The nano-spider moves along a track comprising stitched-together strands of DNA that is essentially a pre-programmed course.
The track exploits DNA's double-helix molecule - a structure of four chemicals that are paired in rungs.
By 'unzipping' the DNA you end up with a track that can be used rather like the teeth in a clockwork mechanism. A cog can move around the teeth, provided it meshes with them.
By using strands that correspond to sequences in the track, the robot can be made to walk, turn left or right as it is biochemically attracted to the next matching stretch.
The spider's 'body' is a common protein called streptavidin. Attached to it are three 'legs' of single-strand enzymatic DNA, which binds to, and then cuts, a particular sequence of DNA. The fourth leg is a strand that anchors the spider to the starting point.
Study leader Milan Stojanovic said: 'After the robot is released from its start site by a trigger strand, it follows the track by binding to and then cutting the DNA strands.'
Once the strand is cut, the leg starts reaching for the next matching stretch of DNA in the track. In this way, the spider is guided down the path set by the researchers.
Eventually, the robot encounters a patch of DNA to which it can bind but cannot cut. At that point, it is immobilised.

A molecular nanorobot dubbed a 'spider' and labeled with green dyes moves along a DNA track to its red-labeled goal

To watch the spider in motion, the researchers used atomic force microscopy which showed the molecular robots following four different paths.
Molecular robots have drawn huge interest because of the allure of programming them to sense their environment and react to it.
For instance, they could note disease markers on a cell surface, decide that the cell is cancerous and needs to be destroyed and then deliver a compound to kill it.
Other DNA walkers have been developed in the past, but they have never ventured more than a few steps, said Hao Yan, a professor at Arizona State University.
Professor Yan said: 'This one can walk about to about 100 nanometers. That's roughly 50 steps.'
The next step is how to make the spider walk faster and how to make it more programmable, so that it can follow many commands on the track and make more decisions.
In a separate study reported in Nature, Nadrian Seeman and colleagues from New York University said they had built a prototype molecular factory.

They used a number of DNA robots to assemble gold particles in different ways in response to chemical commands.

DNA walkers moved past three kinds of DNA machines that handed them a cargo of gold nano-particles, which are clutched with three 'hands'.
'This is the first time that systems of nano-machines, rather than individual devices have been used to perform operations, constituting a crucial advance in the evolution of DNA technology,' said Lloyd Smith, from the University of Wisconsin at Madison, in a commentary also published by Nature.
Nearly £6billion is being invested in research and development of nano products worldwide, according to the Project on Emerging Nanotechnologies, which tracks environmental and health concerns arising from the new technology.


美研制出納米機器人 可清理動脈血管垃圾


  據《每日郵報》5月13日報道,美國哥倫比亞大學科學家近日成功研制出一種由DNA分子構成的“納米蜘蛛”微型機器人,它們能夠跟隨DNA的運行軌跡自由地行走、 移動、轉向以及停止,並且它們能夠自由地在二維物體的表面行走。




納米疫苗特破 RFID晶片要成功了