Tracking single viruses is not a new concept in the scientific field. The concept is, you attach some sort of molecule that will glow to the virus. This will serve as a tracking device for the virus, and you’ll be able to track the virus with very high precision using optical microscopes.
There’s a problem in doing this, however. Since the glowing molecule is usually attached on the outer shell of the virus, this can interfere with the normal activity of the virus. This is why putting the glowing molecule inside the virus is more preferable, and that’s just what this group of researchers from China did.
The researchers replaced the glowing molecule with a quantum dot. A quantum dot is a tiny blob of material that, by virtue of its tiny size, will glow when excited by light. Even better, the color of the glow is tuned by changing the size of the blob, so we can make nearly any color of quantum dot we want.
More details of how they did it, and what they found out, over at Ars Technica.
(Image Credit: National Center for Microscopy and Imaging Research/ Ars Technica)