Subscribe free to our newsletters via your
. Space Industry and Business News .




TECH SPACE
Swiss cheese crystal, or high-tech sponge?
By Charlotte Hsu for BU News
Buffalo NY (SPX) Jan 29, 2014


Created by chemists at the University at Buffalo and Penn State Hazleton, this sponge-like crystal contains many pores that change shape when exposed to ultraviolet (UV) light. In addition, the normally colorless crystal (left) blushes in the presence of UV light, turning red (right). Image courtesy Ian M. Walton.

The sponges of the future will do more than clean house. Picture this, for example: Doctors use a tiny sponge to soak up a drug and deliver it directly to a tumor. Chemists at a manufacturing plant use another to trap and store unwanted gases.

These technologies are what University at Buffalo Assistant Professor of Chemistry Jason Benedict, PhD, had in mind when he led the design of a new material called UBMOF-1. The material - a metal-organic framework, or "MOF" - is a hole-filled crystal that could act as a sponge, capturing molecules of specific sizes and shapes in its pores.

Swiss cheese-like MOFs are not new, but Benedict's has a couple of remarkable qualities:

+ The crystal's pores change shape when hit by ultraviolet light. This is important because changing the pore structure is one way to control which compounds can enter or exit the pores. You could, for instance, soak up a chemical and then alter the pore size to prevent it from escaping. Secure storage is useful in applications like drug delivery, where "you don't want the chemicals to come out until they get where they need to be," Benedict says.

+ The crystal also changes color in response to ultraviolet light, going from colorless to red. This suggests that the material's electronic properties are shifting, which could affect the types of chemical compounds that are attracted into the pores.

Benedict's team reported on the creation of the UBMOF on Jan. 22 in the journal Chemical Communications. The paper's coauthors include chemists from UB and Penn State Hazleton.

"MOFs are like molecular sponges - they're crystals that have pores," Benedict said.

"Typically, they are these passive materials: They're static. You synthesize them, and that's the end of the road," he added. "What we're trying to do is to take these passive materials and make them active, so that when you apply a stimulus like light, you can make them change their chemical properties, including the shape of their pores."

Benedict is a member of UB's New York State Center of Excellence in Materials Informatics, which the university launched in 2012 to advance the study of new materials that could improve life for future generations.

To force UBMOF-1 respond to ultraviolet light, Benedict and colleagues used some clever synthetic chemistry.

MOF crystals are made from two types of parts - metal nodes and organic rods - and the researchers attached a light-responsive chemical group called a diarylethene to the organic component of their material.

Diarylethene is special because it houses a ring of atoms that is normally open but shuts when exposed to ultraviolet light.

In the UBMOF, the diarylethene borders the crystal's pores, which means the pores change shape when the diarylethene does.

The next step in the research is to determine how, exactly, the structure of the holes is changing, and to see if there's a way to get the holes to revert to their original shape.

Rods containing diarylethene can be forced back into the "open" configuration with white light, but this tactic only works when the rods are alone. Once they're inserted into the crystal, the diarylethene rings stay stubbornly closed in the presence of white light.

.


Related Links
University at Buffalo
Space Technology News - Applications and Research






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





TECH SPACE
Spider silk ties scientists up in knots
Madrid, Spain (SPX) Jan 23, 2014
Two years ago, researchers from Iowa State University (USA) published a study which concluded that spider silk conducts heat as well as metals. Now, a team from the University of the Basque Country (Spain) has repeated the experiment and the results throw this discovery into question. This has reaffirmed the need to validate scientific findings before proclaiming their validity in the press. ... read more


TECH SPACE
Swiss cheese crystal, or high-tech sponge?

Microwires as mobile phone sensors

NGC Completes Critical Design Review For James Webb Space Telescope

Spider silk ties scientists up in knots

TECH SPACE
US Navy Accepts General Dynamics-built MUOS Ground Stations

Space squadron optimizes wideband communication constellations

GA-ASI and Northrop Showcase Unmanned Electronic Attack Capabilities

Boeing Transmits Protected Government Signal Through Military Satellite

TECH SPACE
Both payloads for Arianespace's next Ariane 5 flight are mated to the launcher

45th Space Wing Supports NASA Launch

Athena-Fidus receives its "kick" for Arianespace's upcoming Ariane 5 launch

ILS Proton To Launch Yamal 601

TECH SPACE
Lockheed Martin Powers On Second GPS 3 Satellite In Production

India to launch three navigation satellites this year

NGC Wins Contract For GPS-Challenged Navigation and Geo-Registration Solution

20th Anniversary of Initial Operational Capability of the GPS Constellation

TECH SPACE
Red Arrows pilot killed by 'useless' seat mechanism

Swiss to vote in May on fighter deal

Boeing profits surge but tougher 2014 awaits

S. Korea to finalise F-35 jet fighter deal this year

TECH SPACE
Integration brings quantum computer a step closer

Dutch hi-tech group ASML profits dip despite record sales

2-proton bit controlled by a single copper atom

New Technique for Probing Subsurface Electronic Structure

TECH SPACE
Chinese scientists pinpoint source of Yangtze's main tributary

Savanna vegetation predictions best done by continent

China to promote geological information industry

Russian EVA re-attempting installation of Earth-observing cameras

TECH SPACE
Cooperative SO2 and NOx aerosol formation in haze pollution

Made in China for us: Air pollution tied to exports

Delhi says air 'not as bad' as Beijing after smog scrutiny

India's Essar sues Greenpeace for $80 mn for defamation




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement