Creating reversible "smart surfaces" - Engineering - Brief Article

USA Today (Society for the Advancement of Education), June, 2003

Massachusetts Institute of Technology, Cambridge, engineers and colleagues from the University of California, Berkeley, report a unique design of a "smart surface" that can reversibly switch properties in response to an external stimulus. The work paves the way for systems that could release or absorb cells and chemicals from surfaces on demand.

The researchers describe an example of their new approach in which they engineered a surface that can change from water-attracting to water-repelling with the application of a weak electric field: Switch the electrical potential of that field from positive to negative, and the surface reverts to its initial affinity for water.

"This opens the door to a variety of applications, including novel drug-delivery systems and smart templates for the bioseparation of one molecule from another," explains Robert Langer, MIT's Germeshausen Professor of Chemical and Biomedical Engineering.