An international authority in the field of nano-materials, Jay Switzer has always been intrigued by experimentation and discovery. Even his title at UMR – he is the Donald L. Castleman/Foundation for Chemical Research Professor of Discovery – reflects his passion for the quest into the unknown. His specialty involves electrodeposition, a method of “growing" minuscule ceramic materials, layer by thin layer, on a base surface. It’s a process that mimics the way stalagmites grow from mineral deposits in caves.
What is chirality?
Throughout the biological world, in all living things, there are molecules which have a right- and a left-hand form. The two forms are like a person’s right and left hands -- almost identical, only reversed. They are mirror images, but they aren’t superimposable. That is what we mean by chiral.
How does chirality effect pharmaceuticals?
In the process of synthesizing molecules by normal chemical reactions, both the right- and left-hand forms of the molecules tend to be produced. But just as humans have a right- or left-handed preference, one form of the molecule tends to be very active and the other tends to be at best not very active; at worst, toxic.
One example of this is the drug thalidomide, originally used as a sedative. In the 1950s in Europe, thalidomide was prescribed to pregnant women to aid morning sickness. However, while one “hand" of the molecule relieved the woman’s nausea, the other hand was toxic, and caused birth defects.
Another common pharmaceutical example of chirality is the drug ibuprofen, commonly found in over-the-counter pain relievers. In its case, the molecule’s left hand is 100 times more powerful than the right. Approximately one third of all drugs are chiral, including such familiar brands as Lipitor, Zocor, Paxil, Zoloft and Nexium – each of which yield sales of more than $1 billion a year.
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