Look at your window — not out it, but at it. If you could peer inside the pane you would see a molecular mess with tiny particles jumbled together. Researchers at the University of Wisconsin-Madison have developed a new glassmaking technique that eliminates some of the mess. Their glass is stronger and more stable than traditional amorphous-phase glass. Though unsuitable for everyday products like windowpanes or eyeglasses, this new glass may let pharmaceutical companies explore previously unusable drug compounds.
Conventional glasses are made through a process of melting, cooling, and then hardening. Normally, a piece of glass is allowed to cool all at once, and the inner molecules, unable to move freely, tend to get stuck in disarray. Lead author Mark Ediger, a UW-Madison chemistry professor, collaborating with researchers in the UW-Madison School of Pharmacy and the National Institute of Standards and Technology, designed a technique that lets the molecules arrange themselves a little more neatly.
In their work, Ediger and his team build glass layer by layer using a method called vapor deposition. Glass is heated to the point of evaporation and condensed on a cold surface, where the vapor forms an ultrathin liquid film. By adding layers one at a time, each sheet of particles can move into a more organized arrangement before solidifying.
Though the new glasses do not reach the precision of crystals, they are denser and far stronger than traditional glass. Ediger estimates the more stable glass would take at least 10,000 years to form using conventional technology, because the liquid glass would have to cool extremely slowly. The new vapor-deposition method takes about an hour.
Ediger is working With UW-Madison pharmacy professor Lian Yu on possible medical applications for the manufacturing technique. With the new method, Ediger says it may be possible to develop drug compounds that were previously unusable. Stable glass films could also extend the shelf life of existing medical tools like blood-testing and pregnancy-testing kits.