"Sticky ends" of DNA for assembling micro- and nanostructures

The technology of controlled connection of micro- and nanoparticles using DNA has been developedDmitry Safin, Compulenta
Specialists from New York University (USA) managed to solve the problem of spontaneous unification of particles on the surface of which DNA strands are located – "sticky ends".

Each of these "sticky ends" has a specific sequence of nucleotides, and complementary sequences allow the particles to form bonds. The formation of bonds occurs when a certain temperature threshold is reached; with an increase in temperature, they break down. Using this technology, scientists can create and eliminate copies of any structures made of particles of various sizes.

Unfortunately, the described method does not allow controlling individual groups of particles (all elements are connected at once when the temperature decreases), which makes it difficult to form complex structures. American scientists have tried to improve the technology by taking advantage of the ability of DNA strands to form protective "loops" at the ends and bind to neighboring "sticky ends" belonging to the same particle. As it turned out during the experiments, these features manifest themselves with a very rapid decrease in temperature: the particles simply "do not have time" to contact each other, since the "sticky ends" collapse and are neutralized (see graph). To form stable structures, it is necessary to bring together elements in a similar state for a few minutes. Note that in their experiments, the authors used optical tweezers – a device that allows manipulating microscopic objects using laser radiation.

"We have learned to precisely control the formation of bonds between particles," summarizes the lead author of the study Mirjam Leunissen (Mirjam Leunissen). – They can become inert, and then – when approaching – form a strong connection. It turns out something like glue for nanocontacts."

Formation of an array of micrometer-sized particles at a temperature of about 20 ° C.
At the end of the video, the size of the structure decreases, and the particles approach each other.

The report will be published in the journal Nature Materials; the full text of the article can be found here.
Prepared based on the materials of EurekAlert!.

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