Laser light made inside cells

The researchers’ document has get Advance Online Publication in Nature Photonics.

Living biological cells can now be turned into tiny lasers that emit light that can be used to track the spread of diseases, such as cancer.

Biologists often choose lasers to effectively study cells. In both instances, pumping our bodies by using a heart beat of light provided a residing laser beam, like the light got rubbed on inside and of course the chamber shone. The lasers consist of spheres of plastic several micrometers in diameter that are doped with a fluorescent dye and that the cells absorb through a process called endocytosis-although one group also used injected droplets of dyed oil and naturally occurring fat globules.

The first two methods were tested on humans, and the third method was tested using pig cells.

“The fluorescent dyes now used for research and for medical diagnosis are limited because they emit a very broad spectrum of light”, explains Seok Hyun Yun, PhD, of the Wellman Center for Photomedicine at MGH, corresponding author of the report.

The microlasers could change this because their emission spectrum is narrow, in the 500-800 nanometre range, making it easier to label cells with light, says Jeffrey Karp, a bioengineer at Brigham and Women’s Hospital in Boston, Massachusetts.

“Maybe the most interesting application is cell tagging, so you can see how the cells move”, Humar told Quartz.

Because this laser light has optical characteristics that are unique to the cell that the microresonator finds itself in, all the cells tagged this way can be tracked individually for days at a time as they migrate throughout the body.

One day, they say, intracellular lasers could even help determine what a cancer cell is made of, by allowing doctors to analyze the interior with the laser light instead of a biopsy.

Harvard University researchers have created intracellular lasers by implanting microscopic beads and oil droplets into animal cells. The new techniques turn cells themselves into tiny lasers and could make it much easier to tell tagged cells apart, since lasers have a far narrower range of wavelengths.