Don’t worry, if a molecule loses its ability to fluoresce when struck by a laser beam. Just allow it to ‘rest’ in the dark for sometime. It will regain its ability soon. The recovery is found to begin within 30 minutes and is nearly complete after 8 hours of rest, according to a new study by physicist Mark Kuzyk and colleagues at Washington State University. Kuzyk said, It’s almost as if you have a piece of paper that’s yellowed over time, and you put it in a dark room for a day, and it comes back brand-new. The ‘self-healing’ property is discovered in AF455 — a dye compound designed to excel at two-photon absorption. It is a process where the absorption of light energy from a laser can cause a change in the molecule capable of being harnessed for various purposes. It is also during two-photon absorption, when many molecules also glow, or fluoresce, allowing researchers to monitor the process. The two-photon absorption can be used prominently for optical data storage and photolithography — a technique using lasers for assembling microscopic motors parts and nano-sized robots. Kuzyk said, That’s one of the first questions people ask when they see this. They say, ‘isn’t this just the liquid replenishing the stuff that was damaged?’ Nope, this is in a polymer. So you know that it’s the same molecule that’s sitting at that point, as you had before. The molecule itself is actually recovering.