Christopher Campbell, Presidential Fellow 2005-2007
Chemical and Biological Engineering

From The Graduate School Quarterly, Spring 2005:

Chris Campbell is also interested in teaching. During his time at Northwestern, Campbell's work as a teaching assistant in chemical engineering and as a discussion section leader for an applied mathematics has given him opportunities to learn that he enjoys watching students grow, not just academically, but as individuals.

And his research is just as interdisciplinary as his teaching. Campbell 's research involves combining the use of a new technique called wet stamping with the reaction-diffusion process to produce three-dimensional patterns throughout a substance on a very small scale. Campbell notes that because his research has implications for applications across many disciplines, work on the process involves a wide variety of scholars, including graduate students, post-docs and faculty in the fields of analytical and an organic chemistry, chemistry, chemical engineering, theoretical physics, and applied mathematics. "Because everyone is coming from different perspectives, we have very interesting lab discussions," Campbell says.

Reaction-diffusion occurs when chemicals in a solution diffuse in the liquid and also react among themselves. The reactions produce crystals, which create a recognizable pattern in the host substance, thus modifying the structure of the material used. (To see examples, look at the group's Web site, at dysa.northwestern.edu/index_files/Page304.htm.) Campbell notes that, until now, "reaction-diffusion phenomena have not yet been applied in modern material science and technology." The equations related to reaction-diffusion have been used to predict patterns in a number of other fields, however, ranging from population biology to marketing.

Use of the new wet stamping technique makes it possible to produce reaction-diffusion results very quickly, using a very small sample in a very confined space. And because the technique involves a reusable stamp, the process is low-cost, as well.

Depending on the chemicals and host substance used, the resulting crystalline structure may be usable for a number of different functions, such as tiny lenses for telecommunication or sensors or microfluidic channels for testing a very small amount of a biological substance. In fact, using the new technique, Campbell 's lab, led by Professor Bartosz Grzybowski, has produced research grade lenses.

"Smaller, simpler, faster are the buzz words today," Campbell says. "We're working toward the concept of a 'lab on a chip.' The idea is that eventually researchers or doctors will be able to use a PDA to process tests that currently require the use of an entire lab."