Dartmouth researchers develop molecular switch that changes liquid crystal colors
Nanotechnology tool may help in in detecting harmful gases, pathogens, explosives
2013-08-27
(Press-News.org) Dartmouth researchers have developed a molecular switch that changes a liquid crystal's readout color based on a chemical input. This new development may open the way for using liquid crystals in detecting harmful gases, pathogens, explosives and other chemical substances.
The findings appear in the journal Angewandte Chemie. A PDF of the study is available on request.
One of the challenges in the field of molecular switches and machines is the translation of molecular level motion into macroscopic level events by harnessing light or chemical energy -- think of a molecular-sized light switch that can be turned on and off. With an actual light switch, this can be easily done by hard wiring the switch to a light source, but doing this at the nanoscale is challenging.
In their study, the Dartmouth researchers used liquid crystals such as the ones in LCD (liquid crystal display) monitors and TV screens to address this challenge. They synthesized a pH activated molecular switch that can control the long range assembly of a commercially available liquid crystal called NP5. This manipulation changed the readout color of NP5 from purple to green depending on the applied pH, confirming the molecular level motion is responsible for the change in the photophysical properties of the liquid crystal.
The findings open the way for researchers to design molecular switches that produce different liquid crystal readout colors when harmful chemical substances are detected. If these liquid crystals are used as pixels – similar to the ones in LCD screens – researchers may be able to bunch them together and develop groups of sensors that can quickly analyze and detect hazardous materials.
###
Ivan Aprahamian, a co-author and professor of chemistry, is available to comment at ivan.aprahamian@dartmouth.edu. More information about his research is available at Dartmouth Now.
Broadcast studios: Dartmouth has TV and radio studios available for interviews. For more information, visit: http://www.dartmouth.edu/~opa/radio-tv-studios/
END
ELSE PRESS RELEASES FROM THIS DATE:
2013-08-27
Human activities are changing the water chemistry of many streams and rivers in the Eastern U.S., with consequences for water supplies and aquatic life, so reports a new study in the journal Environmental Science and Technology.
In the first survey of its kind, researchers looked at long-term alkalinity trends in 97 streams and rivers from Florida to New Hampshire. Sites ranged from small headwater streams to some of the nation's largest rivers. Over the past 25 to 60 years, two-thirds have become significantly more alkaline.
Alkalinity is a measure of water's ability ...
2013-08-27
New York, NY – Researchers at Columbia University, in collaboration with biologists in Baylor College of Medicine, have made a significant step in understanding and imaging protein synthesis, pinpointing exactly where and when cells produce new proteins. Assistant Professor Wei Min's team developed a new technique to produce high-resolution imaging of newly synthesized proteins inside living cells. The findings were published in the July 9th issue of The Proceedings of the National Academy of Sciences (Volume 110; Issue 28).
Proteins carry out almost every crucial biological ...
2013-08-27
LA JOLLA, CA—August 26, 2013—Scientists at The Scripps Research Institute (TSRI) have found a way to apply a powerful new DNA-editing technology more broadly than ever before.
"This is one of the hottest tools in biology, and we've now found a way to target it to any DNA sequence," said Carlos F. Barbas III, the Janet and Keith Kellogg II Chair in Molecular Biology and Professor in the Department of Chemistry at TSRI.
The breakthrough concerns a set of designer DNA-binding proteins called TALEs, which biologists increasingly use to turn on, turn off, delete, insert ...
2013-08-27
SASKATOON -- When Francis Crick and James Watson discovered the double helical structure of deoxyribonucleic acid (DNA) in 1953, it began a genetic revolution to map, study, and sequence the building blocks of living organisms.
DNA encodes the genetic material passed on from generation to generation. For the information encoded in the DNA to be made into the proteins and enzymes necessary for life, ribonucleic acid (RNA), single-stranded genetic material found in the ribosomes of cells, serve as intermediary. Although usually single-stranded, some RNA sequences were ...
2013-08-27
Each year, millions of people in the United States get a tuberculosis skin test to see if they have the infection that still affects one third of the world's population. But the standard diagnostic test is difficult to give, because a hypodermic needle must be inserted at a precise angle and depth in the arm to successfully check for tuberculosis.
Now, a team led by University of Washington engineers has created a patch with tiny, biodegradable needles that can penetrate the skin and precisely deliver a tuberculosis test. The researchers published their results online ...
2013-08-27
This news release is available in French. The nature of the teenage brain makes users of cannabis amongst this population particularly at risk of developing addictive behaviors and suffering other long-term negative effects, according to researchers at the University of Montreal and New York's Icahn School of Medicine at Mount Sinai.
"Of the illicit drugs, cannabis is most used by teenagers since it is perceived by many to be of little harm. This perception has led to a growing number of states approving its legalization and increased accessibility. Most of the debates ...
2013-08-27
HIV-infected people who carry a gene for a specific protein face a 20-fold greater risk of contracting cryptococcal disease, according to a study published in mBio®, the online open-access journal of the American Society for Microbiology.
Cryptococcus neoformans is the most common cause of fungal meningitis among HIV-infected individuals. While the disease is a risk for everyone with HIV who has a very low level of CD4+ T cells, researchers have discovered that those with the gene for the protein FCGR3A 158V have an immune cell receptor that binds tightly to antibody-bound ...
2013-08-27
August 27, 2013
Nyon, Switzerland
An influential report published in the journal 'Osteoporosis International', recommends 13 best practice standards in the implementation of coordinator-based fracture liaison services (FLS). The report, 'Capture the Fracture: A Best Practice Framework and Global Campaign to Break the Fragility Fracture Cycle' (1), has been been shaped by input from leaders of established Fracture Liaison Services throughout the world and endorsed by the International Osteoporosis Foundation.
Coordinator-based FLS centre around a coordinator, often ...
2013-08-27
Divorce is associated with an increased risk of future depressive episodes but only for those who already have a history of depression, according to a new study published in Clinical Psychological Science, a journal of the Association for Psychological Science.
"Stressful life events like divorce are associated with significant risk for prolonged emotional distress, including clinically-significant depression," notes psychological scientist and lead researcher David Sbarra of the University of Arizona. "At the same time, we know from considerable research that the experience ...
2013-08-27
Philadelphia, Pa. (August 27, 2013) - Techniques developed by astronomers seeking a clear view of objects in space are coming closer to home, as eye care professionals apply the concept of wavefront optics to understanding—and correcting—subtle visual abnormalities of the human eye, according to a special article in the September issue of Optometry and Vision Science, official journal of the American Academy of Optometry. The journal is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health.
Wavefront optics is beginning to transform the way optometrists ...
LAST 30 PRESS RELEASES:
[Press-News.org] Dartmouth researchers develop molecular switch that changes liquid crystal colors
Nanotechnology tool may help in in detecting harmful gases, pathogens, explosives
