Turns out, self-assembling spider silk capsules, crafted by colonies of bacteria, are pretty good at keeping reactive molecules calm.

“We called this ‘Spiderbag’,” said Thomas Scheibel, a protein-chemist-turned-engineer, and coauthor of a study describing the capsules published in Advanced Functional Materials. The tiny spheres, produced by Scheibel and his colleagues at the University of Bayreuth, are about as strong as glass — comparable to the ornamental globes that hang on Christmas trees, “just a few sizes smaller,” Scheibel says.

At once both tough and malleable, the silky containers can sheath proteins that would normally want to react with many things around them. The silk stops the enzymes from unfolding or becoming inactive before they’re needed. Soon, the team says, these capsules will be ready for use in medical diagnostics. Though tiny, the spheres are too large to be injectable. Instead, though he won’t go into details, Scheibel says the capsules could be used as a super-sensitive array capable of detecting performance-enhancing substances  in athletes, for example.