Select your localized edition:

Close ×

More Ways to Connect

Discover one of our 28 local entrepreneurial communities »

Be the first to know as we launch in new countries and markets around the globe.

Interested in bringing MIT Technology Review to your local market?

MIT Technology ReviewMIT Technology Review - logo

 

Unsupported browser: Your browser does not meet modern web standards. See how it scores »


“In malaria, our first measurements indicate that the membrane stiffens as the parasite ages inside the cell,” says Popescu. “In fact, the cell membrane behaves much like a guitar string. The tighter or stiffer it is, the higher the pitch produced. So, our technique can be regarded as an incredibly sensitive microphone.” In the long term, he says, this kind of optical imaging may have clinical applications: it could yield a way to help reverse such diseases.

Meanwhile, a separate research group in the Spectroscopy Lab, led by postdoctoral associate Christopher Fang-Yen, is using optical interferometry to watch the activity of individual neurons. With this technique, Fang-Yen was able to detect small twitches of a few nanometers in nerve fibers and single neurons during an action potential, or electrical impulse. “Many researchers have observed a transient swelling in nerves during the action potential,” says Fang-Yen. “We’re interested in imaging these motions to detect signaling between neurons.”

Illuminating the mechanical changes in activated neurons may provide a new way of probing the activity of neural circuits, particularly for studies of learning and memory. Current optical imaging techniques for neurons use fluorescent markers, or dyes, that stain for things like calcium ions, an indirect measure of electrical activity. However, Fang-Yen says fluorescence methods are marred by photobleaching, phototoxicity, and slow time scales. The optical technique developed by the Spectroscopy Lab creates nanometer-scale images in less than a millisecond, and it’s not subject to photobleaching or phototoxicity.

John Sedat, professor of biochemistry at the University of California, in San Francisco, sees this optical imaging technique as a new perspective in an evolving field. “There’s a kind of miniature revolution taking place in microscopy,” he says. “This is an example of physics people coming into biology and bringing in a lot of new ways of seeing things.”

0 comments about this story. Start the discussion »

Credit: Gabriel Popescu

Tagged: Biomedicine

Reprints and Permissions | Send feedback to the editor

From the Archives

Close

Introducing MIT Technology Review Insider.

Already a Magazine subscriber?

You're automatically an Insider. It's easy to activate or upgrade your account.

Activate Your Account

Become an Insider

It's the new way to subscribe. Get even more of the tech news, research, and discoveries you crave.

Sign Up

Learn More

Find out why MIT Technology Review Insider is for you and explore your options.

Show Me