Scientists at National Taiwan University have designed a remarkable molecular structure that mimics the complex layered patterns often seen in nature.
Led by Professor Yi-Tsu Chan, the team created a stable, two-layer nanocage that can even act as a miniature chemical reactor, producing gold nanoparticles within its hollow core.
Their findings were recently published in the Journal of the American Chemical Society.
Nested structures—where one form is enclosed within another—are everywhere in biology. Viruses use protective shells, while living cells rely on compartments to organize countless chemical reactions.
These designs allow organisms to carry out multiple functions efficiently in confined spaces. Reproducing this same level of sophistication in the lab, however, has long been a challenge for chemists.
Professor Chan’s team overcame this hurdle by developing a new type of molecular building block that can assemble itself into a layered cage.
The resulting structure consists of two geometric shapes: an inner octahedron enclosed by an outer truncated tetrahedron. Together, they form a giant supramolecule weighing more than 44,000 daltons—an unusually large and stable structure at the molecular scale.
The breakthrough was possible thanks to the careful design of two complementary chemical connectors, known as ligands.
These ligands attach to metal ions in a way that is both flexible and selective, guiding the molecules to self-assemble into the desired shape. The approach also prevents competing side reactions that might otherwise destabilize the structure, giving the nanocage an impressive resilience.
To visualize the design, the researchers turned to some of the most advanced tools in modern science, including nuclear magnetic resonance (NMR), small-angle X-ray scattering (SAXS), cryo-electron microscopy, and high-resolution electron microscopy.
These methods confirmed the fine details of the nanocage, showing its stability and precision down to the single-molecule level.
Beyond its striking architecture, the nanocage also has practical uses. Its empty interior can act as a nanosized reaction chamber, similar to how cells use compartments to control chemical activity. In one experiment, the researchers successfully produced gold nanoparticles inside the nanocage, demonstrating its potential as a tiny, controllable factory.
“This work shows how carefully designed molecular interactions can lead to precise and durable architectures that echo nature’s complexity,” said Professor Chan. “We believe our approach opens new opportunities in advanced materials, nanotechnology, and catalysis.”
The study not only represents a milestone in molecular design but also points to future applications where such nanocages could act as custom-built reactors, storage vessels, or even delivery systems, expanding the boundaries of what is possible in chemistry and nanotechnology.
