Miniature labs made easy

Where technology is concerned, smaller often means more expensive. But using a method developed by UW-Madison biomedical engineers, biologists soon may be able to fabricate elaborate palm-sized "laboratories" more easily and for about a quarter of the cost of current methods.

Now the process requires expensive, specialized equipment, a clean room and hours of time. But with standard microscope slides, polycarbonate adhesive gaskets called Hybriwells, channel masks, a photopolymer and UV light, Research Scientist Glennys Mensing and Associate Professor of Biomedical Engineering David Beebe can make multilayered devices in about a half hour.

They fabricate the devices like a chef makes an open-faced sandwich. The microscope slide forms the base. Next is a Hybriwell, which comes with pull-off backing and adheres to the slide's edges like a gasket. To create channels in the Hybriwell, the two fill the space between it and the slide with a photopolymer, and lay a mask, or diagram of the channel, atop the Hybriwell. Then they expose the layers to ultraviolet light, which bonds the photopolymer to the slide and Hybriwell and creates channels where the mask blocks the UV light. By adding additional Hybriwells and following the same process, Mensing and Beebe can create separate or interconnected layers tailored to their specifications.

Because they can make these labs with multiple capabilities, including filtering, diluting, mixing and readout, researchers could use them to synthesize chemicals, conduct genetic analyses, screen drugs, analyze water samples and more — all on a very small scale.

Beebe and Mensing are patenting the process through the University of Wisconsin Foundation. The patent application is one of nine related to microfluidics technology that Beebe and various co-inventors have filed since April 2001.