Super-sized nanocage could deliver bigger drug cargoes

Nanocages are tiny artificial containers that can be used to deliver therapeutics to a target destination in the body. But some drug molecules are like gifts that are too big for a standard-sized nanocage "box.“

Now researchers from the University of Cambridge describe how they have built a super-sized nanocage that could be used to deliver larger drug cargoes.

Rational control over the self-assembly of these types of cages generally poses considerable challenges. So instead of following traditional self-assembly methods, the team decided to use a simple building block process inspired by natural biological systems.

Using the new method, they were able to build progressively larger artificial nanocages, with the largest cage having an enclosed volume greater than 92 cubic nanometers – the largest ligand-enclosed inner cavity volume ever made.

Larger cages have been reported, but they have more open ligand frameworks, which are not as useful because these cages have not been able to bind cargoes. Prospective "guest" molecules slip out between the widely-spaced bars, unless they are covalently tethered to the "host" framework.

First author Dr. Kai Wu, a postdoctoral researcher in the Nitschke lab in the Yusuf Hamied Department of Chemistry, said, "The findings of this study are important because they demonstrate how we are able to create ever-larger complex, functional structures using simple building blocks.".

Image source: Wu et al. (2023), Nature Synthesis.