Navigation Links
Purple light means go, ultraviolet light means stop

A new membrane developed at the University of Rochester's Laboratory for Laser Energetics blocks gas from flowing through it when one color of light is shined on its surface, and permits gas to flow through when another color of light is used. It is the first time that scientists have developed a membrane that can be controlled in this way by light.

Eric Glowacki, a graduate student at the University's Laboratory for Laser Energetics, and Kenneth Marshall, his advisor, invented the membrane. Marshall will present their findings at the annual conference of the International Society for Optics and Photonics (SPIE) in San Diego on Aug. 1.

The membrane is a piece of hard plastic riddled with tiny holes that are filled with liquid crystals and a dye. When purple light illuminates the surface of the membrane, the dye molecules straighten out and the liquid crystals fall into line, which allows gas to easily flow through the holes. But when ultraviolet light illuminates the surface, the dye molecules bend into a banana shape and the liquid crystals scatter into random orientations, clogging the tunnel and blocking gas from penetrating.

Controlling a membrane's permeability with light is preferable to controlling it with heat or electricity two readily used alternative methods for several reasons, Glowacki said. For starters, light can operate remotely. Instead of attaching electrical lines to the membrane, a lamp or a laser can be directed at the membrane from a distance. This could allow engineers to make much smaller, simpler setups.

Another advantage is that the color of the light illuminating the membrane can be changed precisely and almost instantaneously. Other methods, like heating and cooling, take a relatively long time and repeated heating and cooling can damage the membrane.

Also, light does not have the potential to ignite a gas, which could be a crucial benefit when working with hydrocarbons or other flammable gases. Lastly, the amount of light energy needed to switch the membrane on and off is miniscule.

Creating the membrane is a multi-step process. First, a circular hard plastic chip is bombarded with a beam of neutrons to make the tiny, evenly spaced holes that are about one-hundredth of a millimeter in diameter. The chip is then dipped in a solution of liquid crystals and dye, and the mixture fills the holes through capillary action. The final product is spun in a centrifuge to remove the excess liquid crystals from the surface.

The membrane could be useful in controlled drug delivery and industrial processing tasks that require the ability to turn the flow of gas on and off as well as in research applications.


Contact: Alan Blank
University of Rochester

Related medicine news :

1. Purple Day March 26th: The United States Goes Purple in Support of Epilepsy Awareness
2. Purple Cupcake Production on the Rise Nationwide
3. ClearWay Minnesota(SM) Shines a Spotlight on a Reinvented Tobacco Industry
4. Cyndi Lauper, Lady Gaga Put Spotlight on Women and HIV
5. Virtual Global Highlights Top Ten Misconceptions about Cloud Computing
6. Research highlights role of protein pair in obesity regulation
7. Highlights of major physics conference in Washington, D.C.
8. Defective signaling pathway sheds light on cystic fibrosis
9. Lack of morning light keeping teenagers up at night
10. Fluorescent probes light up cancerous tumors
11. Lighthouse To Help Relief Efforts In Haiti
Post Your Comments:
(Date:11/25/2015)... ... November 25, 2015 , ... For the first time, ... Two Organizations, One Beat ” campaign. The partnership between the two groups began in ... in MAP International’s cause. , MAP International was founded in 1954 and is an ...
(Date:11/25/2015)... ... 25, 2015 , ... Dental professionals who would like to become more proficient ... attend Dr. Mark Iacobelli’s Advanced Implant Mentoring (AIM) CE course. Courses will be held ... the co-founders of Advanced Implant Mentoring (AIM), Dr. Iacobelli and Dr. D’Orazio are proud ...
(Date:11/25/2015)... (PRWEB) , ... November 25, 2015 , ... The McHenry ... a recent successful appellate decision obtained by Attorneys Francisco J. Botto and Alex C. ... v. Illinois Workers’ Compensation Comm’n, 2015 IL App (2d) 130884WC. , According to court ...
(Date:11/25/2015)... ... November 25, 2015 , ... SCOTTSDALE, AZ) - Today, ... specializing in both surgical and non-surgical treatments, announced the expansion of his private ... Plastic Surgery. , Highly trained and nationally recognized for his natural approach, ...
(Date:11/25/2015)... ... November 25, 2015 , ... In an ongoing Clinical ... Center (RMC) in Chicago, IL, UV Angel is evaluating the efficacy of its product ... intensive care units (totaling 30 beds) from May 2014 through October 2015 at a ...
Breaking Medicine News(10 mins):
(Date:11/26/2015)... and Markets ( ) has announced the addition of ... - Rise in Cardiac Disorders and Growing Awareness among People ... Boston scientific and others. ... others. --> The market is dominated by ... scientific and others. Asia ...
(Date:11/26/2015)... 26, 2015 ... "2016 Future Horizons and Growth Strategies ... Market: Supplier Shares, Country Segment Forecasts, Competitive ... offering. --> ) has ... Future Horizons and Growth Strategies in the ...
(Date:11/26/2015)... 26, 2015 ) ... Administration of High Viscosity Drugs" report to ... announced the addition of the "Self Administration ... offering. --> Research and Markets ( ... "Self Administration of High Viscosity Drugs" ...
Breaking Medicine Technology: