AP Centerpiece: MIT researchers powering electronics with photosynthesis
- MARK PRATT, Associated Press Writer
Thursday, September 23, 2004

(09-23) 14:11 PDT BOSTON (AP) --

"Eat your spinach," Mom used to say. "It will make your muscles grow, power your laptop and recharge your cell phone... "

But researchers at the Massachusetts Institute of Technology say they have used spinach to harness a plant's ability to convert sunlight into energy for the first time, creating a device that may one day power laptops, mobile phones and more.

That was until Shuguang Zhang, associate director of MIT's Center for Biomedical Engineering, discovered that protein building blocks called detergent peptides could be manipulated to keep the proteins alive up to three weeks while in contact with electronics.

"Stabilizing the protein is crucial," said Zhang, who collaborated with researchers from MIT, the University of Tennessee and the U.S. Naval Research Laboratory, including electrical engineers, nanotechnology experts and biologists. "Detergent peptide turned out to be a wonderful material to keep proteins intact."

A top layer of glass was coated underneath with a conductive material and a thin layer of gold to aid the chemical reaction. In the middle, the spinach-peptide mixture sits on a soft, organic semiconductor that prevents electrical shorts and protects the protein complexes from a bottom layer of metal.

By shining laser light on the "sandwich," researchers were able to generate a tiny current. While one device by itself can't generate much energy, billions of them together could produce enough electricity to power a device.

The researchers suggest the technology could be used as a backup energy supply for battery-powered portable devices.

"We have crossed the first hurdle of successfully integrating a photosynthetic protein molecular complex with a solid-state electronic device," said Marc Baldo, an assistant professor of electrical engineering and computer science at MIT.

URL: http://sfgate.com/cgi-bin/article.cgi?file=/news/archive/2004/09/23/financial1711EDT0297.DTL