12/07/2005
Loss of a Giant Who Thought Small
I just learned that during our Panama Canal cruise we lost one of the giants in the field of chemistry. Richard Smalley died on October 28 of non-Hodgkin’s lymphoma at the age of 62. Smalley and Robert Curl Jr., his colleague at Rice University, burst into the limelight in 1985 with their discovery of the “buckyball”. Buckyball was the nickname given the soccer-ball- shaped molecule of 60 carbon atoms they decided to call buckminsterfullerene after the architect Buckminster Fuller, known for his geodesic domes that resemble the buckyball.
It was as if a dam had burst. The discovery of the strange new form of carbon spurred research all over the world and in Japan Sumio Iijima discovered the carbon nanotube. The carbon nanotube is a molecule in which the walls of the tube resemble a sheet of chicken wire folded to form a cylinder with the carbons arranged in hexagons as in chicken wire. There are also multi- walled nanotubes consisting essentially of nanotubes nesting in nanotubes. The study of “fullerenes” became a whole new field of endeavor and in 1996 Smalley and Curl shared the Nobel Prize in Chemistry with Sir Harold Kroto of Great Britain for opening up a new world of “nano” materials.
The carbon buckyballs and nanotubes were found to have amazing properties that make them exciting for physicists, electronic device engineers and even mechanical engineers. For example, it appears that carbon buckyballs and nanotubes are the strongest substances in the universe! Carbon nanotubes not only have exceptional mechanical strength but they’re also light and highly elastic. They can be bent to sharp angles without failing. In the November 25 issue of Science there’s a paper titled “Super-Compressible Foamlike Carbon Nanotube Films” by Anyuan Cao at the University of Hawaii at Manoa and coworkers from the University of Florida in Gainesville and Rensselaer Polytechnic Institute in Troy, New York. Nanotube foams may uses in electromechanical systems and as coatings for mechanical damping and energy-absorbing applications. I’m wondering about bulletproof vests.
The week before, in the November 18 Science, there was a paper by Jia Chen of IBM’s Thomas J. Watson Research Center and coworkers from Duke University in which they report the emission of bright infrared light from carbon nanotubes. Carbon nanotubes can be electrical conductors or semiconductors depending on how they’re bent or twisted. The possibilities of using them as tiny switches or in memory applications are in the dreams of electronic device engineers. You can put stuff inside buckyballs and nanotubes. Put the right element in a buckyball and you have a superconductor. Some have proposed stuffing buckyballs or nanotubes with hydrogen for use in fuel cells. Nanotubes may someday be used instead of plasma or liquid crystals in TV displays.
A most exciting potential application is the use of nanotubes as agents for delivering drugs directly to the sites of cancers. This application was one dear to Smalley, who helped push Congress to approve the $1-billion-a-year National Nanotechnology Initiative. According to an article by Robert Service on Smalley’s death in the November 4 Science, Smalley predicted that the program could lead to nanotech drugs capable of wiping out certain forms of cancer. Service quotes Smalley in his prophetic 1999 testimony: “I may not live to see it. But, with your help, I am confident it will happen.”
Smalley’s colleagues at Rice pioneered a nano approach that delivers not a drug, but heat to cancerous tumors in animal studies. They used nano particles coated with gold to target tumors and then shone infrared light on the particles. The infrared light travels through healthy tissue but heats the gold- coated particles, cooking the tumor cells to death. Since that work, published two years ago, others have successfully used carbon nanotubes to kill tumors.
The nano work at Rice wasn’t all as serious as the work on cancer. I hope that before he died Smalley got to enjoy seeing his fullerenes being used in the construction of a neat little “nanocar”. I read about the nanocar in an article by Bethany Halford in the October 24 Chemical and Engineering News (C&EN). The nanocar will not appear in your dealer’s showroom – its wheelbase is less than five nanometers and it has no engine. (To give you a feeling for the size of the car, I measured a hair on my wrist to be 50,000 nano meters. Its wheelbase is less than1/10,000th the width of my hair!) A model pictured in the C&EN article showed the nanocar to be simply an H-shaped chassis with fullerene wheels, possibly buckyballs.
Chemistry professor James Tour and his group spent 8 years working on the car! Apparently, forming the organic compound chassis was a relative snap, taking only 6 months to accomplish. The hard part was attaching the wheels. They placed the car on a smooth gold surface and had to heat the surface to above 170 degrees Centigrade before it would move (the fullerene wheels are strongly attracted to the gold). The Rice group is convinced the nanocar rolls rather than slides across the surface since it moves perpendicular to the axles. They’ve also been able to drive it by moving the tip of a scanning tunneling microscope in front of it. There’s an electrostatic attraction between the car and the tip so they can drag the car around. They reportedly have also built a nanotruck that presumably can carry nanocargo.
When I started this column, I had planned to mention Smalley’s death in passing but as I came across tributes to him I realized that he was a very special person. He has been termed the “grandfather of the entire field of nanotechnology” by Anna Barker, deputy director of the National Cancer Institute and “a Moses” by Jim Heath of the California Institute of Technology. Smalley’s colleague S. Ward Casscells, in a tribute in the November 7 C&EN, said that, only a few hours before his death at the famed M. D. Anderson Cancer Center in Houston, Smalley was conferring with his students on results in the lab obtained the previous day.
Heath, who was a grad student of Smalley’s, describes Smalley as one who didn’t consider any task as beneath him, even after he became famous. In the November 11 Science, Heath tells of the time someone dropped a screwdriver into the vacuum chamber in which buckyballs were discovered. The handle dissolved in oil in the bottom of the chamber, which was 10 feet tall. The chamber had to be cleaned out. Smalley and Heath stripped down to their underwear and each took turns holding the other by the ankles, lowering him down into the chamber to do the cleaning!
In Casscells’ words, Smalley “made of the small a whole new world and shared this enormous gift with memorable dedication, patience and generosity.”
Speaking of generosity, I want to thank our Editor, Brian Trumbore, for including old Bortrum in a festive celebration of Brian’s mother’s birthday last Saturday. The day was highlighted by a visit to the outstanding Russian show at the Guggenheim Museum in New York and a most enjoyable lunch at a small French restaurant, with Lamb creator Harry Trumbore and LT rounding out the group.
Allen F. Bortrum
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