Self-assembly has been taken to the next level

A group of physicists has created a new way to self-assemble particles, an advance that offers new hope
for making complex and innovative materials at the microscopic level.
Self-assembly technology, which came out in the early 2000s, offers scientists a way to "pre-program" particles that allow them to build materials without human intervention — just as
IKEA furniture can self-assemble.
The breakthrough, published in Nature, is the immersion of emulsions – oil droplets in water and their application
in the self-assembly of the folder.
The folder is a unique shape that can be theoretically predicted
by the order in which the oil droplets interact.

This self-assembly process draws on knowledge from the field of biology, utilizing colloids to mimic the folding
of proteins and RNA.
In this work, the researchers created tiny oil-based droplets in water that possess arrays
of DNA sequences that serve as "instructions" for assembling.
These droplets first assemble into flexible strands and then collapse or fold
sequentially through viscous DNA molecules.
This folding gave rise to more than a dozen types of folders, and further specificity could encode more than
half of the 600 possible geometries.

Jasna Brujic, a professor in NYU's Department of Physics and one of the researchers, explains: "Being able to pre-program colloidal structures provides us with the means
to create materials with complex and innovative properties.
Our work shows how to uniquely create hundreds of self-assembled geometries, opening up new possibilities
for the creation of next-generation materials.
”

The researchers also include Angus McMullen
, a postdoc in the Department of Physics at New York University.
The scientists emphasized the counterintuitive and pioneering nature of this approach: it doesn't require a large number of blocks to encode precise shapes, and its folding technique means that only a few blocks are needed, as each can take multiple forms
.
Brujic explains: "Unlike puzzles, where each piece is different, our process uses only two types of particles, which greatly reduces the variety
of building blocks needed to encode a particular shape.
What's innovative is that it uses a protein-like fold, but it's 1,000 times longer than protein — about one-tenth
the size of a hair.
These particles first combine to form a chain, which then folds according to pre-programmed interactions, guiding the chains through complex paths to form unique geometric shapes
.
The ability to acquire a lexicon of shapes opens the way for further assembly into larger materials, just as proteins polymerize stratified in biology to create cell
separations.
”

Images describing this process and the resulting shapes can be downloaded from Google Drive
.