Leaded crystal and common glass may look similar, but the crystal is made of a rigid scaffolding of atoms, while the glass is a disordered, atomic slurry.
Researchers at the University of Wisconsin-Madison have developed a method for crafting some of the most stable glasses ever formed--materials that are strong and durable like crystal and yet free of the confining properties of an ordered atomic skeleton. They hope the new method will enable drug manufacturers to take advantage of chemicals that had been too insoluble as crystals and too unstable as glasses.
The findings, appearing in the Dec. 8, 2006, issue of Science, announce a method to deposit glass materials layer by layer as a vapor onto a surface with an ideal temperature for yielding stable glasses, an advancement over earlier vapor deposition efforts and different from the more traditional practice of quenching molten material.
Supported by the National Science Foundation and the Department of Agriculture, chemist Mark Ediger and his colleagues at the university collaborated with researchers at the National Institute of Standards and Technology to craft and study stable glasses. One such glass, formed from the anti-inflammatory drug indomethacin, is a test for how pharmaceuticals could benefit from the new technique.
The latest wonder drugs work only if they arrive in the body where they are needed and at the right concentration at the right time. Some potential pharmaceuticals are hindered by being too crystalline--not dissolving quickly enough, or at all, in the body--or too glassy, breaking down too quickly or in uncontrollable ways.
A detailed University of Wisconsin press release is available at: http://www.news.wisc.edu/releases/13279.html
By National Science Foundation