Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Microcantilevers are masters of measurement: Detergents, study of diseases may benefit from Rice University research

Abstract:
Devices that look like tiny diving boards are a launching platform for research that could improve detergents and advance understanding of disease.

Rice University researcher Sibani Lisa Biswal and Kai-Wei Liu, a graduate student in Biswal's lab who recently earned her doctorate at Rice, used microcantilevers as ultrasensitive measuring devices to study how lipid bilayers interact with surfactants.

Microcantilevers are masters of measurement: Detergents, study of diseases may benefit from Rice University research

Houston, TX | Posted on June 2nd, 2011

Their results were reported online this month in the American Chemical Society journal Analytical Chemistry.

Lipid bilayers are membranes that surround the cells of every living organism. Along with specific membrane proteins, they act as gatekeepers that allow ions, proteins and other essential molecules to pass into the cell. Individual lipid molecules in the bilayer have a hydrophilic head and two hydrophobic tails. They naturally aggregate into two-layered sheets, with the heads pointed out and the water-avoiding tails pointed inward.

Liu and Biswal, an assistant professor in chemical and biomolecular engineering, described in a previous paper how to attach lipid bilayers to microcantilevers, which have traditionally been used as analytical biosensors. A protective coating on the thin gold layer makes the top of the "diving board" inert, so the membranes attach themselves to and spread out over the silicon dioxide bottom. The exchange of energy as the membrane meets the solid platform changes the surface tension and bends the cantilever enough to be measured by a laser sensor. Any change to the membrane will alter the bend, which can be measured with nanometer resolution, Biswal said.

In the new work, the researchers introduced varying concentrations of lysolipids to the supported lipid bilayers. Lysolipids are surfactants, compounds that lower the surface tension of liquids and can act as detergents, among other things. Like the molecules that make up lipid bilayers, lysolipid molecules have a hydrophilic head but only one hydrophobic tail.

Liu and Biswal found that in low concentrations, lysolipid molecules wedged themselves into the bilayer as their water-hating tails cozied up to the membrane's hydrophobic inner ring; this changed the surface tension on the cantilever.

All of these forces can be measured, Biswal said. "The cantilever naturally wants to bend with whatever force the membrane puts on it," she said.

In high concentrations, lysolipid monomers form micelles, rings of molecules that interact with the membranes and disrupt the hydrophobic interactions that keep them together.

Depending on their strength (determined by the chemical makeup of their hydrophobic tails), the micelles can either weaken the membranes by pulling lipid molecules away or destroy the membranes completely.

That is precisely what you want a detergent to do to a stain, and the new technique would be very useful for fine-tuning cleaning agents, Biswal said.

"A vast amount of research has gone into detergency," she said. "There are a lot of detergencies based on enzymes, the biomolecules that cleave peptide bonds. A lot of stains are organic molecules. If you can cleave them, you can clean surfaces much better."

Biswal sees other potential for the technique. "We're interested in using this as a general platform for looking at small molecules," she said.

Liu is pursuing one such path. She is studying how hepatitis C peptides behave in the presence of a microcantilever-mounted membrane. "This could be a way to probe how viruses are able to enter cell membranes or disrupt proteins on their surfaces," she said.

Biswal suggested that carbon-60 atoms -- the buckyballs discovered at Rice in 1985 -- might also be a good subject. "We don't know enough about how nanomaterials interact with cell membranes, and since buckyballs are naturally hydrophobic, they might be interesting to investigate."

The Robert A. Welch Foundation funded the research.

####

For more information, please click here

Contacts:
Mike Williams
PHONE: 713-348-6728

Copyright © Rice University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Nano Ruffles in Brain Matter: Freiburg researchers decipher the role of nanostructures around brain cells in central nervous system function October 31st, 2014

Gold nanoparticle chains confine light to the nanoscale October 31st, 2014

'Nanomotor lithography' answers call for affordable, simpler device manufacturing October 31st, 2014

Device invented at Johns Hopkins provides up-close look at cancer on the move: Microscopic view of metastasis could give insight about how to keep cancer in check October 31st, 2014

Nanomedicine

Nano Ruffles in Brain Matter: Freiburg researchers decipher the role of nanostructures around brain cells in central nervous system function October 31st, 2014

Production of Biocompatible Polymers in Iran October 30th, 2014

Amorphous Coordination Polymer Particles as alternative to classical nanoplatforms for nanomedicine October 30th, 2014

'Electronic skin' could improve early breast cancer detection October 29th, 2014

Discoveries

Nano Ruffles in Brain Matter: Freiburg researchers decipher the role of nanostructures around brain cells in central nervous system function October 31st, 2014

Gold nanoparticle chains confine light to the nanoscale October 31st, 2014

'Nanomotor lithography' answers call for affordable, simpler device manufacturing October 31st, 2014

Device invented at Johns Hopkins provides up-close look at cancer on the move: Microscopic view of metastasis could give insight about how to keep cancer in check October 31st, 2014

Announcements

Nano Ruffles in Brain Matter: Freiburg researchers decipher the role of nanostructures around brain cells in central nervous system function October 31st, 2014

Gold nanoparticle chains confine light to the nanoscale October 31st, 2014

'Nanomotor lithography' answers call for affordable, simpler device manufacturing October 31st, 2014

Device invented at Johns Hopkins provides up-close look at cancer on the move: Microscopic view of metastasis could give insight about how to keep cancer in check October 31st, 2014

Nanobiotechnology

Tiny carbon nanotube pores make big impact October 29th, 2014

Molecular beacons shine light on how cells 'crawl' October 27th, 2014

Breakthrough in molecular electronics paves the way for DNA-based computer circuits in the future: DNA-based programmable circuits could be more sophisticated, cheaper and simpler to make October 27th, 2014

NYU Researchers Break Nano Barrier to Engineer the First Protein Microfiber October 23rd, 2014

NanoNews-Digest
The latest news from around the world, FREE





  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More














ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE