The stuff of dreams
How does one visualize thought? Well, by pressing the open tip of an electrolyte-filled glass pipette much thinner than a human hair against the membrane of an individual brain cell, researchers can isolate a patch and identify the current flowing through individual ion channels on a cell's membrane. This technique is known as the patch-clamp method and it allows a peek at the electrical activity of individual cells.
"From a physicist's point of view, ion channels on a cell's membrane look very much like the transistors in an integrated circuit," says Professor of Electrical and Computer Engineering Dan van der Weide. "Ion channels are proteins that behave as gate-like channels, opening and closing to regulate the flow of ions into and out of the cell." Prairie Technologies in Madison is a manufacturer of scientific instruments for researchers who study the inner workings of the brain in order to determine how the brain processes information for learning and memory. Such research could also lead to a better understanding of diseases like epilepsy and Alzheimer's.
Dan van der Weide and Prairie are now working together to develop a new tool for monitoring neuronal activity. It is similar to the patch-clamp method in that it offers a very specialized look at the electrical activity of a cell. In the patch-clamp method, the pipette probe must make physical contact with the cell and once in place cannot be moved. It's also a relatively slow method of transferring information from the cell. The van der Weide method overcomes these limitations. This technology uses microwaves to monitor the capacitance of an ion channel as it opens and closes.
"He's sort of making the equivalent of the cellular phone as compared to the land line," says Prairie Technologies' president Mike Szulczewski. "In the future, we'll be able to move the probe around rather than leave it on one position and because it's wireless, it doesn't have to make physical contact with the cell. Right now he's got it so that we can monitor signals. We haven't yet manufactured a moveable patch clamp, but that is the goal."
Prairie is working with the College of Engineering through a National Institutes of Health Small Business Technology Transfer grant. The program helps small businesses commercialize university research while allowing the university to maintain control of the technology. "It is a collaboration that has developed over the years that we have worked together," says Szulczewski. "We were working with Dan for about a year before he came to the university. It was his coming to Wisconsin that really allowed this collaboration to flourish and develop." van der Weide joined the College of Engineering in 2000 as part of the UW's Nanophase Cluster-Hiring Initiative, part an innovative public-private partnership matching financial support from the State of Wisconsin with private funding from alumni and donors through the University of Wisconsin Foundation and the Wisconsin Alumni Research Foundation.
"We're a small company and we're just now starting to grow," says Szulczewski. "We have grown through developing technology with university professors. People like Dan van der Weide being in Wisconsin give us the ability to grow these technologies in our own backyard."
This story is also featured on the Wisconsin Technology Network, http://www.wistechnology.com/article.php?id=1583