Dartmouth researchers create 'green' process to reduce molecular switching waste

December 15, 2014

HANOVER, N.H. - Dartmouth researchers have found a solution using visible light to reduce waste produced in chemically activated molecular switches, opening the way for industrial applications of nanotechnology ranging from anti-cancer drug delivery to LCD displays and molecular motors.

The study appears in the Journal of the American Chemical Society. A PDF is available on request.

Chemically activated molecular switches are molecules that can shift controllably between two stable states and that can be reversibly switched -- like a light switch -- to turn different functions "on" and "off." For example, light-activated switches can fine-tune anti-cancer drugs, so they target only cancer cells and not healthy ones, thereby eliminating the side effects of chemotherapy.

But such switches typically generate waste and side products that are problematic. One way of making these processes cleaner is by using light energy, similar to how photosynthesis operates in nature. In their experiments, the researchers show that a merocyanine-based photoacid derivative can effectively be used in a switching process that is fast, efficient and forms no wastes.

"We address a bottleneck that's been hampering the field for decades -- what to do with the accumulated salts and side products when activating such switches," says co-author Ivan Aprahamian, an associate professor of chemistry. "Acids, bases and other compounds need to be constantly added to the mix to make sure the system can be switched, but within a few cycles there is so much waste that it interferes with the switching process. We found a neat solution by coupling an efficient photoacid to our chemically activated hydrazone switch. We showed the system can be efficiently modulated more than 100 times with no accumulation of waste or degradation. We are using visible light to accomplish this, so in reality we are converting light energy into a chemical output, similar to what happens in photosynthesis. You can look at this as a 'green' process that closes the loop in a nanotech-related process, and it will reduce waste in future industrial applications of molecular switches."
-end-
Associate Professor Ivan Aprahamian is available to comment at ivan.aprahamian@dartmouth.edu

Broadcast studios: Dartmouth has TV and radio studios available for interviews. For more information, visit: http://www.dartmouth.edu/~opa/radio-tv-studios/

Dartmouth College

Related Industrial Applications Articles from Brightsurf:

Ultrafast laser experiments pave way to better industrial catalysts
Arizona State University's Scott Sayres and his team have recently published an ultrafast laser study on uncharged iron oxide clusters, which could ultimately lead to the development of new and less-expensive industrial catalysts.

A biomimetic membrane for desalinating seawater on an industrial scale
Reverse osmosis is one of the most widely used techniques for the desalination of water.

Industrial-strength brine, meet your kryptonite
A thin coating of the 2D nanomaterial hexagonal boron nitride is the key ingredient in a cost-effective technology developed by Rice University engineers for desalinating industrial-strength brine.

New control technique could improve accuracy of industrial robots
The brains of humans and other animals often practice feedforward control as they are very good at whole-system modeling.

Major new study charts course to net zero industrial emissions
A major new study by an interdisciplinary team of researchers finds that it is possible -- and critical -- to bring industrial greenhouse gas emissions to net zero by 2070.

Using renewable electricity for industrial hydrogenation reactions
The University of Pittsburgh's James McKone's research on using renewable electricity for industrial hydrogenation reactions is featured in the Journal of Materials Chemistry A's Emerging Investigators special issue.

Industrial melanism linked to same gene in 3 moth species
The rise of dark forms of many species of moth in heavily polluted areas of 19th and 20th century Britain, known as industrial melanism, was a highly visible response to environmental change.

Mapping industrial 'hum' in the US
Using a dense sensor network that scanned the United States between 2003 and 2014, researchers have identified areas within the country marked by a persistent seismic signal caused by industrial processes.

Industrial 3D printing goes skateboarding
Plastic pulled from the waste stream can find new use with the Gigabot X, an open source industrial 3D printer.

Lobster's underbelly is as tough as industrial rubber
Flip a lobster on its back, and you'll see that the underside of its tail is split in segments connected by a translucent membrane that appears rather vulnerable when compared with the armor-like carapace that shields the rest of the crustacean.

Read More: Industrial Applications News and Industrial Applications Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.