Human Cells Transformed into Tiny Lasers

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.

Researchers Matjaz Humar and Seok Hyun Yun at Harvard Medical School uncovered three ways to turn human cells into functional lasers.

First, they injected cells with tiny oil droplets to form a cavity that could be filled with fluorescent dye. When an external pulse of light was directed at the droplet, the cells emitted light in a narrow beam.

Secondly, the team used polystyrene beads, which were ingested by a type of white blood cell, to carry out functions similar to the oil droplets.

In a third technique, pictured above, the scientists exploited fatty droplets that existed within living cells to emit a beam of light.

Humar told New Scientist that the process was "actually super-easy."

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

The new method could also make is much easier to distinguish between different cells.

Today, fluorescent dyes are commonly used to tag living cells and emit light, but they produce a broad range of wavelengths that can make it challenging to differentiate one tagged cell from another.

The new method of turning cells into tiny lasers makes it much easier to distinguish between tagged cells since lasers have a more narrow range of wavelengths.

In the future, scientists could potentially give every cell in the human body its own unique laser signature. This could help to track the spread of tumor cells, for example, or monitor how cells respond to inflammation.

The findings were published in the journal Nature Photonics.

via Phys.org, Gizmodo and New Scientist

Lasers may bring to mind military-grade weaponry or the pew-pew sounds of science fiction blasters, but powerful laser tech can be used for less destructive purposes. Scientists and engineers are now aiming lasers at persistent problems like air turbulence, inoperable tumors and drug addiction. Here's a look at the ways zapping something with a beam of light can actually help rather than hurt.

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