A team of Vanderbilt scientists have invented the world’s smallest version of the periscope and are using it to look at cells and other microorganisms from several sides at once. The researchers have dubbed their devices „mirrored pyramidal wells.“ They consist of pyramidal-shaped cavities molded into silicon whose interior surfaces are coated with a reflective layer of gold or platinum. They are in dimension about the width of a human hair and can be made in a range of sizes to view different-sized objects. When a cell is placed in such a well and viewed with a regular optical microscope, the researcher can see not only the top of the cell, but several sides simultaneously. „This is something biologists almost never see,“ says team member Chris Janetopoulos, assistant professor of biological sciences.
The Vanderbilt group is not the first to make microscopic pyramidal wells, but it is the first to apply them to make 3D images of microorganisms. In 2006, a group of scientists in England created pyramidal micromirrors and applied them to trapping atoms. And last spring researchers at the National Institute of Standards and Technology used similar structures to track nanoparticles.