Microscopic implants trap, amplify light, letting researchers track cellular activity
Matjaž Humar and Seok-Hyun Yun
Biologists often use lasers to probe cells. Now, for the first time, cells have returned fire.
Harvard University researchers have created intracellular lasers by implanting microscopic beads and oil droplets into animal cells. When energized by an outside laser pulse, an implant traps and amplifies light and then emits a laser pulse of its own. “It’s a wonderful way of coupling optics to cells to learn about biological processes,” says chemist Richard Zare of Stanford University. The microscopic lasers, reported July 27 in Nature Photonics, could allow scientists to track the motion of thousands of individual cells.
The new technique is far from the first to coax cells to generate their own light. Biologists routinely scrutinize cells under the microscope with the help of fluorescent dyes and proteins that glow when energized by an external laser pulse (