Metallofullerenes

In chemistry, a metallofullerene is a molecule composed of a metal atom trapped inside a fullerene cage.

Simple metallofullerenes consist of a fullerene cage, typically C
80, with one or two metal atoms trapped inside. Recently, research has produced metallofullerenes that enclose small clusters of atoms, such as Sc
3N@C
80, Y
3N@C
80, and Sc
3C
2@C
80. The '@' symbol in the formula indicates that the atom(s) are encapsulated inside the cage, rather than being chemically bonded to it.

Fullerenes in a variety of sizes have been found to encapsulate metal atoms in this way.

One particular metallofullerene with gadolinium at its core is up to 40 times better as a contrast agent in magnetic resonance imaging scans for diagnostic imaging. Metallofullerenes may also provide ways to carry therapeutic radioactive ions to cancerous tissue.

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