The Heart of Bone
A team of MIT researchers led by civil engineer and materials scientist Markus Buehler has finally unraveled the structure of bone—a long-standing mystery—with almost atom-by-atom precision. Doing so took many years of analysis by some of the world’s most powerful computers, results that were confirmed by laboratory experiments.
Buehler says the biggest question was how two different materials—a soft, flexible biomolecule called collagen and a hard, brittle form of the mineral apatite—combine to form something that is simultaneously hard, tough, and slightly flexible.
The constituents are so different that “you can’t take these two materials individually and understand how bone behaves,” Buehler says. Hydroxyapatite is like chalk, he says: “It’s very brittle. If you try to bend it even a little, it breaks into pieces.” Collagen, on the other hand, is what gelatin is made of—the very epitome of a wobbly substance.
The team found that “tiny hydroxyapatite grains [are] embedded in the collagen matrix,” allowing the two materials to “each contribute the best of their properties,” Buehler says. “Hydroxyapatite takes most of the forces in the material, whereas collagen takes most of the stretching.”
The new understanding of bone’s molecular structure and function could help in determining what goes wrong in diseases such as osteoporosis and brittle bone disease.
Keep Reading
Most Popular
Large language models can do jaw-dropping things. But nobody knows exactly why.
And that's a problem. Figuring it out is one of the biggest scientific puzzles of our time and a crucial step towards controlling more powerful future models.
OpenAI teases an amazing new generative video model called Sora
The firm is sharing Sora with a small group of safety testers but the rest of us will have to wait to learn more.
Google’s Gemini is now in everything. Here’s how you can try it out.
Gmail, Docs, and more will now come with Gemini baked in. But Europeans will have to wait before they can download the app.
This baby with a head camera helped teach an AI how kids learn language
A neural network trained on the experiences of a single young child managed to learn one of the core components of language: how to match words to the objects they represent.
Stay connected
Get the latest updates from
MIT Technology Review
Discover special offers, top stories, upcoming events, and more.