Press Release 05-121
An Open and Shut Case at the Nanoscale

New nano-valve can start and stop a molecular flow repeatedly

The stick-like rotaxane molecule is surrounded by a ring that can move up and down. Credit and Larger Version

July 19, 2005

Chemists at UCLA have created the first reversible nano-valve: a molecular machine that they can open and close like a faucet whenever they want. Among the many potential applications are nanoscale drug delivery systems that could release pharmaceuticals at very precise points within the body, or even within a single cell.

UCLA chemist Jeffrey Zink and his colleagues based their valve on rotaxane: a molecule that will switch back and forth from one stable configuration to another depending on its chemical environment. They collaborated with a team led by Fraser Stoddart, director of the California NanoSystems Institute at UCLA, who has already shown how these switchable rotaxanes can be used in molecular electronics.

The development of the new valve was supported by a Nanotechnology Interdisciplinary Research Team Grant from the National Science Foundation. Zink, Stoddart and their coworkers published their results in the July 8, 2005, online edition of The Proceedings of the National Academy of Sciences, and in the July 19, 2005, print edition of that journal.

For more information, see the UCLA news release.

-NSF-

Media Contacts
M. Mitchell Waldrop, NSF (703) 292-7752 mwaldrop@nsf.gov
Stuart Wolpert, UCLA (310) 206-0511 stuartw@college.ucla.edu

Program Contacts
Filbert J. Bartoli, NSF (703) 292-8339 fbartoli@nsf.gov

Principal Investigators
Jeffrey I. Zink, UCLA (310) 825-1001 zink@chem.ucla.edu
Fraser Stoddart, UCLA (310) 206-7078 stoddart@chem.ucla.edu

Related Websites
UCLA News Release: http://newsroom.ucla.edu/page.asp?RelNum=6306
California Nanosystems Institute: http://www.cnsi.ucla.edu/mainpage.html
The PNAS article, "A Reversible Molecular Valve": http://www.pnas.org/cgi/reprint/0504109102v1

The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2009, its budget is $9.5 billion, which includes $3.0 billion provided through the American Recovery and Reinvestment Act. NSF funds reach all 50 states through grants to over 1,900 universities and institutions. Each year, NSF receives about 44,400 competitive requests for funding, and makes over 11,500 new funding awards. NSF also awards over $400 million in professional and service contracts yearly.

 Get News Updates by Email 

Useful NSF Web Sites:
NSF Home Page: http://www.nsf.gov
NSF News: http://www.nsf.gov/news/
For the News Media: http://www.nsf.gov/news/newsroom.jsp
Science and Engineering Statistics: http://www.nsf.gov/statistics/
Awards Searches: http://www.nsf.gov/awardsearch/