Self-assembling nanorobots-transformers
Biotechnologists have learned how to create nano-"transformers" from DNA strands
Today, most experiments with DNA-based nanomachines use a special class of methods for their assembly, which in the scientific community are known collectively as "DNA origami". In this technique, the basis for any details of biomachines is a long single DNA chain, which is woven into the desired three–dimensional object using short "hairpins" of several nucleotides - DNA bricks.
As noted by Hendrik Dietz from the Technical University of Munich (Germany), such nanoconstructions are very limited in their application and their shape and function can be set only once during the initial assembly.
The problem, according to him, lies in the assembly technology itself – to connect the origami parts and weave a single DNA chain, strong chemical bonds between the nucleotides themselves are used, which are extremely difficult to break. Dietz and his colleagues found a solution to this problem using the same principles that living cells use when assembling and working complex protein molecules and transporting nucleotides to the assembly site of DNA strands.
They began to use as basic elements not nucleotides or "hairpins" of them, but ready-made blocks, a kind of "lego cubes" of DNA molecules. Such blocks can be connected to other "cubes" under certain conditions and form arbitrary three-dimensional structures, and then break up into parts when the temperature, chemical composition of the medium or other parameters change.
At the bottom – micrographs of "nanotransformers", at the top – their schematic images.
Drawing by H. Dietz from the Technische Universitat Munchen press release
Arm-waving nanorobot signals new flexibility in DNA origami – VM.
As with real lego bricks, these building blocks can be programmed so that they can only be assembled in a certain way. This makes it possible to assemble complex, extremely mobile and multifunctional nano-robots from them, capable of self-assembling after arriving at the place of work in the form of a "soup" of DNA particles, and then disassembling into parts when they are not needed.
To demonstrate the efficiency of this technology, Dietz and his colleagues assembled several "transformers" capable of working as engines, manipulator arms and other tools. Their operation can be controlled by changing the concentration of ions in the solution, which causes them to either turn on or off. In turn, an increase in temperature causes such "transformers" to change shape and reassemble, while simultaneously serving as a source of energy for such transformations.
However, the main advantage of this technology is its simplicity for engineers – such robots can be assembled, according to Dietz, directly on a computer using a special programming language similar to the processor's machine language. Scientists hope that this flexibility and convenience will help bring the technology of DNA robots to a practical level.
I wonder if they will be able to assemble a nanorobot,
who was drawn by C. Hohmann for the aforementioned press release? – VM.
Portal "Eternal youth" http://vechnayamolodost.ru27.03.2015