The mesmerising glow of a jellyfish could soon see safer lasers available to map human cells.
At the moment, two types of lasers are used to produce light.
The first, a conventional laser, emits identical photons that have bounced around inside a cavity to produce light. This is the type of laser that you would use to highlight parts of a diagram in a presentation.
The second, a polariton laser, passes photons back and forth between excited molecules. These are released and reabsorbed within the laser – allowing it to produce light.
But both types have drawbacks. A conventional laser uses a massive amount of energy and is unviable to scale up, while a polariton laser will only operate at very low temperatures.
As polariton lasers use less energy they are safer for medical applications (as they are less destructive). It was this insight that lead scientists to begin work on a polariton laser that could be used at room temperature.
Jellyfish proteins just happened to be their answer. The barrel-shaped proteins are unique in that their light-emitting molecules are spaced widely enough to produce laser light at room temperature.
Together with his team, Gather constructed the laser by securing a thin film of the jellyfish protein between two mirrors. The pulse of an external blue light was the key to success in getting the jellyfish protein to produce light.
While fluorescent proteins have already been embedded into living tissue, they can only differentiate about 10 cell types because of the broad range of wavelengths that they emit. Within a laser, this problem will be circumnavigated as the spectrum of light is much narrower.
Gather explains the benefits of the new low-energy laser:
You label each cell with a different laser, and then you just collect this light. You can look at the wavelengths of the light and say, ‘Aha, this is this cell, because the laser light it emits has this particular wavelength’.
If you work in living tissue, you don’t want to strain the tissue or the cells with too much energy.
Thank you jellyfish!