February 24, 2007 — Improved understanding of nanostructures such as molecular switches will be the catalysts of dramatic changes in the understanding of disease in the coming decade, predicts nanobiologist James R. Heath.
Heath, founder of the California NanoSystems Institute, spoke at the first William G. Spitzer Lecture, held Feb. 21, 2007 and sponsored by the Viterbi School’s Mork Family Department of Chemical Engineering and Materials Science.
The changes will play out first on the battlefield of cancer, Heath told a crowded auditorium of USC faculty, staff and students in an afternoon lecture entitled “Nanosystems Biology and New Technologies for in vitro and in vivo Diagnostics of Cancer.”
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Left to right: Theodore Tsotsis, chair of the Mork Family Department of Chemical Engineering and Materials Science, guest speaker James Heath of Caltech, and Professor Anupam Madhukar of the Mork Department.
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“Medicine is at an apex right now and in the next few years, it’s going to become almost transformative,” said the Caltech chemistry professor. “It’s going to play out with cancer first, because that’s basically a first world disease, it’s something where really great databases exist and there’s a lot of experimental data.”
In his address, Heath said he has been using PET (positron emission tomography) scans rather than other, more conventional imaging techniques to study cancer and other diseases at the molecular level. PET scans are able to detect cellular metabolism, which increases in the early stages of cancer, and determine disease before it causes structural damage. Other imaging techniques such as CT (computed tomography) scans are only able to image tissue or cell structure, which means abnormalities would not appear until a tumor had already begun to develop. Heath’s team has been designing nano/molecular switches and nanowires that can help create platforms for early detection of cancer and other diseases.
“Often times, as cells go from healthy to cancerous, they’ll become independent of many things, like oxygen, and they really turn off the consumption of glucose,” Heath said. “So if you look at glucose metabolism in the body, then you can identify (early on) where the tumors are beginning to grow. With the right medication, even within two hours, you can see the tumors shut down. It’s a stunning result.”
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Cancer cell
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Nanotechnology as it relates to medicine or other industries focuses on the development of nano materials, devices and systems with dimensions measured in nanometers — 1/80,000th the width of a human hair, or the length of 10 hydrogen atoms placed end to end. At that scale matter behaves in bizarre, unfamiliar patterns, quite unlike what is seen even at microscopic scale, and novel phenomena and patterns have been observed.
Scientists believe that the potential for materials and devices that small is great in many industries, but medicine and computer science are likely to be among the first to benefit. In everyday life, nanotechnology has already had an impact on some of the products people commonly use, such as sunscreen lotions and wrinkle-free fabrics.
Fabricating Nanometer Scale Structures
Heath is interested in understanding how to fabricate, assemble and utilize nanometer scale structures. He works with a diverse set of problems, and consequently, has extensive collaborations with other groups at UCLA and other institutions, as well as with industrial research groups.
Part of his work has also focused on investigations of the synthesis and properties of nanocrystal quantum dots and quantum wires, as well as quantum phase transitions in quantum dot solids. Recently, he turned his attention to developing tiny nano/molecular switches.
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Overlay of PET scan data with CT/MRI data allows physicians to pinpoint the location of a tumor.
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His molecular switches made headlines in the Jan. 25, 2007 issue of the journal
Nature, in which he and co-investigators reported “the successful demonstration of a large-scale, ‘ultra-dense’ memory device that stores information using reconfigurable molecular switches.” Caltech reported that the research represented “an important step toward the creation of molecular computers that are much smaller and could be more powerful than today’s silicon-based computers.” The 160-kilobit molecular memory chip – about the density of a molecule -- was touted as something that could be ready for commercial memory devices by 2020.
Heath is also known for his involvement in the discovery of “buckyballs,” which are nanoparticles composed of 60 carbon atoms arranged in a hexagon-faced object. While conducting his Ph.D. work in chemistry at Rice University, he was the principal student on a team that discovered C60 and the fullerenes, now known as buckyballs, which later led to a Nobel Prize.
Spitzer Lecture
The Spitzer Lecture was named in honor of physicist William G. Spitzer, who was a member of the USC Viterbi School faculty from 1963-1993.
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William Spitzer
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Renowned in the field of semiconductor physics, Spitzer was the founding chair of the Viterbi School’s original Materials Science Department, and known for his pioneering contributions to the understanding of free carrier absorption, plasmon-phonon coupling, local mode absorption and transport across Schottky barriers. He later served as chair of the Physics Department (1969-72), dean of Natural Sciences (1983-89), and interim provost (1993).
In 1969, Spitzer was awarded the USC Research Award. In 1982, he received the USC Raubenheimer Distinguished Faculty Award and, in 1989, USC bestowed on him its highest honor, the USC Presidential Medallion.
Spitzer’s son, Matthew Spitzer, thanked the Viterbi School and the Mork Family Department of Chemical Engineering and Materials Science for creating the annual Spitzer Lecture as a tribute to his father, who was unable to attend the lecture.