Hold the ice: NYU chemists reveal behavior of antifreeze molecules

November 19, 2012

Chemists at New York University have discovered a family of anti-freeze molecules that prevent ice formation when water temperatures drop below 32 degrees Fahrenheit. Their findings, which are reported in the latest issue of the Proceedings of the National Academy of Sciences (PNAS), may lead to new methods for improving food storage and industrial products.

"The growth and presence of ice can be damaging to everything from our vehicles to food to human tissue, so learning how to control this process would be remarkably beneficial," says co-author Kent Kirshenbaum, an associate professor in NYU's Department of Chemistry. "Our findings reveal how molecules ward off the freezing process and give new insights into how we might apply these principles elsewhere."

A common misperception is that water necessarily freezes when temperatures reach 32 degrees Fahrenheit or zero degrees Celsius. Not so, scientists point out.

"Nature has its own anti-freeze molecules," explains co-author Michael Ward, chair of NYU's Department of Chemistry. "We simply don't have the details on how they work."

To explore this topic, the researchers created artificial, simplified versions of protein molecules that, in nature, inhibit or delay freezing. These molecules were placed in microscopic droplets of water, and ice formation was monitored by video microscopy and X-ray analysis. The experiments allowed the researchers to determine which critical chemical features were required to stymie ice crystallization.

The experimental results showed that there are two ways the molecules adopt anti-freeze behavior. One, they work to reduce the temperature at which ice begins to form, and, two, once ice does begin to form, they interact in ways that slow down its accumulation.

The researchers then investigated the molecules' structural features that might explain these capabilities. Their observations showed molecules act as "ice crystallization regulators." Ice has a crystal structure, and the anti-freeze molecules may associate with these crystal surfaces in ways that inhibit the growth of these crystals, thus delaying or halting the freezing process.
-end-
The study's other co-authors were: Mia Huang, an NYU doctoral student at the time of the study and now a postdoctoral fellow at Yale University; David Ehre, a postdoctoral fellow in NYU's Department of Chemistry; Qi Jiang, an NYU doctoral student; and Chunhua Hu, an NYU research scholar.

The research was supported by the National Science Foundation (CRIF/CHE-0840277, CHE-1152317) and by the NSF Materials Research Science and Engineering Center (MRSEC) Program (DMR-0820341).

NYU's center is one of 30 MRSECs in the country. These NSF-backed centers employ interdisciplinary and multidisciplinary materials research to address fundamental problems in science and engineering. For more, go to http://mrsec.as.nyu.edu.

New York University

Related Chemistry Articles from Brightsurf:

Searching for the chemistry of life
In the search for the chemical origins of life, researchers have found a possible alternative path for the emergence of the characteristic DNA pattern: According to the experiments, the characteristic DNA base pairs can form by dry heating, without water or other solvents.

Sustainable chemistry at the quantum level
University of Pittsburgh Associate Professor John A. Keith is using new quantum chemistry computing procedures to categorize hypothetical electrocatalysts that are ''too slow'' or ''too expensive'', far more thoroughly and quickly than was considered possible a few years ago.

Can ionic liquids transform chemistry?
Table salt is a commonplace ingredient in the kitchen, but a different kind of salt is at the forefront of chemistry innovation.

Principles for a green chemistry future
A team led by researchers from the Yale School of Forestry & Environmental Studies recently authored a paper featured in Science that outlines how green chemistry is essential for a sustainable future.

Sugar changes the chemistry of your brain
The idea of food addiction is a very controversial topic among scientists.

Reflecting on the year in chemistry
A lot can happen in a year, especially when it comes to science.

Better chemistry through tiny antennae
A research team at The University of Tokyo has developed a new method for actively controlling the breaking of chemical bonds by shining infrared lasers on tiny antennae.

Chemistry in motion
For the first time, researchers have managed to view previously inaccessible details of certain chemical processes.

Researchers enrich silver chemistry
Researchers from Russia and Saudi Arabia have proposed an efficient method for obtaining fundamental data necessary for understanding chemical and physical processes involving substances in the gaseous state.

The chemistry behind kibble (video)
Have you ever thought about how strange it is that dogs eat these dry, weird-smelling bits of food for their entire lives and never get sick of them?

Read More: Chemistry News and Chemistry 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.