Scientists trap bacteria with optical tractor beam

Studying bacterial cells and other cell cultures at high resolutions is now much easier thanks to a team of researchers from Germany.

Scientists at Bielefeld University have found a way to trap bacteria with a laser beam, simplifying the process of imaging cells with powerful microscopes.

Typically, scientists affix cells to a substrate before placing them under the lens of a microscope. The process risks augmenting the cells and tainting the sample -- whether blood or bacteria.

"Our new method enables us to take cells that cannot be anchored on surfaces and then use an optical trap to study them at a very high resolution," Thomas Huser, a professor of physics at Bielefeld, said in a news release. "The cells are held in place by a kind of optical tractor beam."

The new process for microscope imaging uses a beam of infrared laser light. The laser excites internal forces in the cell that keep it trapped within the beam. A second laser can be used to move and turn the trapped sample.

"The principle underlying this laser beam is similar to the concept to be found in the television series 'Star Trek,'" said Huser.

Scientists incorporated the the technique into the superresolution fluorescence microscopy imaging process, allows them to secure high-resolution images of cell samples from a variety of angles.

Researchers described the process in the journal Nature Communications.