Hello,

We noticed you're browsing in private or incognito mode.

To continue reading this article, please exit incognito mode or log in.

Not an Insider? Subscribe now for unlimited access to online articles.

The Heart of Bone

MIT researchers have decoded the complex structure that gives bones their strength

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.

bone and mineral crystal
Bone combines a collagen ­protein molecule (top) and a hydroxyapatite mineral crystal.

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.

July/August MIT News cover
This story is part of the July/August 2013 Issue of the MIT News magazine
See the rest of the issue
Subscribe

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.

Tech Obsessive?
Become an Insider to get the story behind the story — and before anyone else.

Subscribe today
Next in MIT News
Want more award-winning journalism? Subscribe to Insider Plus.
  • Insider Plus {! insider.prices.plus !}*

    {! insider.display.menuOptionsLabel !}

    Everything included in Insider Basic, plus the digital magazine, extensive archive, ad-free web experience, and discounts to partner offerings and MIT Technology Review events.

    See details+

    Print + Digital Magazine (6 bi-monthly issues)

    Unlimited online access including all articles, multimedia, and more

    The Download newsletter with top tech stories delivered daily to your inbox

    Technology Review PDF magazine archive, including articles, images, and covers dating back to 1899

    10% Discount to MIT Technology Review events and MIT Press

    Ad-free website experience

/3
You've read of three free articles this month. for unlimited online access. You've read of three free articles this month. for unlimited online access. This is your last free article this month. for unlimited online access. You've read all your free articles this month. for unlimited online access. You've read of three free articles this month. for more, or for unlimited online access. for two more free articles, or for unlimited online access.