By Lee Ha-na
Dr. Yun Seok-hyun and Dr. Malte Gather are physicists at Massachusetts General Hospital who have spent last four years developing a laser made from human cells. This laser was made from the same three elements that make up any laser: lasting material (gas, crystal, etc.), a pump source (laser radiation, flash lamp, etc.), and an optical cavity. This lasting material is a substance in which electrons are excited to a higher energy level, thus releasing that energy as laser light.
The doctors’ lasting material is an altered human kidney cell that produces green fluorescent protein (GFP), which is what allows jellyfish to emit bright light. These cells were cultured and placed between two mirrors. This was the optical cavity, or a “cell sandwich,” according to Dr. Yun. They produced the laser by sending pulses of blue light through it, which caused a laser beam to shoot out into one direction.
The physicists were able to see the cell, which by then was grey in color with glowing spots, through a microscope. These spots were the laser.
So what’s the hype over this laser?
Such human laser can activate cancer-treating medications via photodynamic therapy. Light-sensitive compounds can be injected into the bloodstream of patients to detect tumors and other cancerous cells. Usually these compounds are activated outside of the body, but this type of internal treatment will produce a more accurate diagnosis.
But for the time being, Dr. Yun will focus on his human laser detecting changes within cells. The light from this laser passes through cells millions of times before leaving as a laser beam. He says this type of light can be used to monitor cell activity due to its unprecedented sensitivity, similar to the way a high-speed camera functions.
Does this mean humans might be able to shoot lasers out of their eyes?
Dr. Yun says yes, although the light would be more comparable to that of a flashlight than a death ray. He also adds that the brain might be able to control a light source implanted in the eyes.