Researchers filmed nanoparticle self-assembly for the first time.

Note translator: in my previous post there was a link to this news (although she herself would soon be half a year), but it seemed to me that she deserved a separate post.

The restoration of the T-1000, which had been shredded before, is not the same as the self-assembly of nanoparticles, but the ideas are similar. For the first time in history, scientists observed the process of self-assembly of nanoparticles in real time. The particles in the video do not exceed a measly 12 nanometers. It is so small that the Argonne National Laboratory of the US Department of Energy had to use a transmission electron microscope located in their Nanomaterial Center to capture fast-moving nanoparticles.

To force them to reassemble, the researchers coated gold nanoparticles (NPs) with positively charged cetyltrimethylammonium ions (CTA +) and negatively charged citrate ions in a liquid water cell. Under the influence of an electron beam emitted by a microscope, the resulting high-energy electrons reduced the total positive charge of CTA + covering gold nanoparticles, as a result of which electrostatic repulsion forces between them also decreased, leading to the union of individual particles into one-dimensional structures. Negatively charged particles coated with citrate ions, on the contrary, proved to be stable, regardless of the radiation intensity.

This process is not something new, but for the first time it was possible to capture it on video.
Making the particles move is a great success. Although the experiments are still primitive, they can lead to more significant particle manipulations at the nano level. In the end, researchers will be able to use these movements to create microscopic machines (acting like biological nanosystems in our bodies), new materials, and even energy.

Full research on the link: In Situ Visualization of Self-Assembly of Charged Gold Nanoparticles
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In the process of work I found another interesting news from this area:

Scientists have synthesized a substance capable of self-assembly after the destruction of the structure. In water, a new gel restores the shape that it loses without a liquid medium.

The hero of the cult action movie "Terminator 2: Judgment Day", the robot T-1000, was made of liquid metal and is capable of recovery after any mechanical destruction. While this superpower remains a fantasy, but engineers at Cornell University are already developing something similar. Scientists from the laboratory of Danya Lyuo created a new hydrogel, which can restore the initial form after its violation. The gel itself is a liquid, but in water it “remembers” and restores a certain shape. Of course, this is not a liquid metal: gel refers to the so-called metamaterials, whose properties depend not only on their chemical composition, but also on their structure. The basis of the gel is a mixture of synthetic DNA molecules tangled together. Separate DNA chains are excellent building blocks for materials capable of self-assembly, since DNA molecules are “programmed” to communicate with each other in separate sections according to the key-lock principle.

The gel consists of small spheres with a diameter of one micrometer, formed by "tangled" DNA. Scientists themselves compare these areas with bird nests, in which there are many voids. "Nests", in turn, are linked by long strands of DNA. Since nucleic acids are constructed from separate sites - nucleotides, the sequence of nucleotides during synthesis can be changed by changing the properties of the molecule. In their development, scientists used DNA from arbitrarily arranged nucleotides. In the future, Cornell plans to synthesize DNA with predetermined nucleotide sequences in order to make the ability for self-assembly more perfect.