21: Physical Chemistry of the Future
Historically physical chemistry was the interface between physics and chemistry, where discoveries in physics were applied to the solution of chemical problems. Today of course physical chemists are also involved in the application and development of physical tools for the solution of biological and even medical problems. Since biology promises a nearly infinite reservoir of interesting problems to be solved, we can anticipate increasing activity in that direction. For physical chemists such as myself, this presents a conundrum. Biological problems are often problems of great complexity and interrelationships with other problems. One solution leads to another problem, and so on. A complete solution of a single problem could involve a lifetime of effort. So the physical chemist is best advised to collaborate with an established biologist, or MD, even though this has not been my style. With few exceptions, my collaborations have been largely confined to graduate students and postdocs. In my case the important exceptions have been Mark Davis in the Stanford Medical School, and Phillippa Marrack of the National Jewish Hospital who have provided cell lines that have been essential for our work in immunology.
A continuing trend has, of course, been the determination of the structural properties of macromolecules of biological significance, such as the active sites of enzymes. A recent example where spin labels were used is to be found in Gaffney et. al.
Physical chemistry promises a continuing source of new techniques such as single molecule tracking and functional magnetic resonance imaging, both of which have become mature sciences in recent years. And of course, in my own areas of interest, there remain some subjects, such as critical phenomena, lipid membranes, molecular electronic structure theory, and protein folding that remain challenging in themselves without regard to specific applications. Continuous advances in computing power strengthen many techniques in current use and are likely to make new methods possible.