Seeing the Invisible

Human beings have been trying to figure out the elementary composition of the universe since the era of ancient Greece. Democritus, an ancient Greek philosopher, created atomic theory. In the atomic theory, everything is composed of “atoms” (from the Greek meaning “can’t be cut”) and these atoms are physically indivisible.1 The ancient Greeks speculated on …

The Atomic Difference Between Diamonds and Graphite

Everything is made of atoms. Usually these atoms are strongly connected to one another, in an amazing variety of configurations. But atoms are so tiny, how can we possibly understand the structure of matter at the atomic level? You probably have seen pictures of molecules or materials, zoomed in to the atomic level, which show …

Spying on chameleon nanoparticles inside living cells

If you are exposed to nanoparticles, you might think they would move around inside your body unchanged. However, it would be more accurate to think of them as tiny chameleons, constantly changing their properties as they move from one biological environment to another. Nanoparticles’ large surface area-to-mass ratio, which causes them to be highly reactive, …