Lasers emit highly concentrated, amplified light. Usually it takes a complex array of crystals, gels or gases to amplify light particles, known as photons, as they bounce around between mirrors inside laser machines. But now scientists have found another way: using engineered living cells that can perform the feat.
The project took place at the Wellman Center for Photomedicine in Massachusetts. The key to this breakthrough involved the use of the widely studied protein known as green fluorescent protein (GFP). This protein, which was first discovered in jellyfish, has (as the name implies) the property of generating light.
In an article published in Nature Photonics, researchers Malte Gather and Seok Hyun Yun describe how a solution made from GFP was used in combination with a mirrored chamber to create a laser. From this preliminary test, Gather and Yun were able to determine how much GFP was required to create the laser light. Using this result, they then moved ahead to genetically engineer mammalian cells that could express the GFP at the required levels.
The researchers report that they were able to create bright laser pulses that lasted a few nanoseconds with a single cell. Amazingly the cells were not damaged during the production of the laser light but were able to withstand hundreds of pulses. Furthermore, the spherical shape of the cell itself acted as a lens “refocusing the light and inducing emission of laser light at lower energy levels than required for the solution-based device.”
Although there are no immediate plans to use this technology, the erosion of the barrier between optical technologies and biology could open many doors in therapy and research. Gather tells PhysOrg.com that they “hope to be able to implant a structure equivalent to the mirrored chamber right into a cell, which would the next milestone in this research."
Credit: Nature Photonics and Malte Gather, Wellman Center for Photomedicine, Mass. General Hospital