Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > 'Smart' Bio-nanotubes Developed; May Help in Drug Delivery

Abstract:
In the future nanotubes could be designed to encapsulate and then open up to deliver a drug or gene

'Smart' Bio-nanotubes Developed; May Help in Drug Delivery

Santa Barbara, CA | August 02, 2005

Materials scientists working with biologists at the University of California, Santa Barbara have developed "smart" bio-nanotubes — with open or closed ends — that could be developed for drug or gene delivery applications.

The nanotubes are "smart" because in the future they could be designed to encapsulate and then open up to deliver a drug or gene in a particular location in the body. The scientists found that by manipulating the electrical charges of lipid bilayer membranes and microtubules from cells, they could create open or closed bio-nanotubes, or nanoscale capsules.The news is reported in an article to be published August 9 issue of the Proceedings of the National Academy of Sciences. It is currently available on-line in the PNAS Early Edition. See: this link.

UCSB - smart bio-nanotubes
"Smart" bionanotubes. Lipid protein nanotubes made of microtuble protein (made of tubulin protein subunits shown as red-blue-yellow-green objects) that is coated by a lipid bilayer (drawn with yellow tails and green and white spherical heads) which in turn is coated by tubulin protein rings or spirals. By controlling the relative amount of lipid and protein it is possible to switch between two states of nanotubes with either open ends (shown in the center) or closed ends with lipid caps (shown on the left), a process which forms the basis for controlled chemical and drug encapsulation and release. A top view of the nanotubes and a magnified region is shown on the right. The image was created by and Copyright © Peter Allen.
Click on image for larger version.

The findings resulted from a collaboration between the laboratories of Cyrus R. Safinya, professor of materials and physics and faculty member of the Molecular, Cellular, and Developmental Biology Department, and Leslie Wilson, professor of biochemistry in the Department of Molecular, Cellular and Developmental Biology and the Biomolecular Science and Engineering Program. The first author of the article is Uri Raviv, a post-doctoral researcher in Safinya's lab and a fellow of the International Human Frontier Science Program Organization. The other co-authors are: Daniel J. Needleman, formerly Safinya's graduate student who is now a postdoctoral fellow at Harvard Medical School; Youli Li, researcher in the Materials Research Laboratory; and Herbert P. Miller, staff research associate in the Department of Molecular, Cellular and Developmental Biology.

The scientists used microtubules purified from the brain tissue of a cow for their experiments. Microtubules are nanometer-scale hollow cylinders derived from the cell cytoskeleton. In an organism, microtubules and their assembled structures are critical components in a broad range of cell functions –– from providing tracks for the transport of cargo to forming the spindle structure in cell division. Their functions include the transport of neurotransmitter precursors in neurons.

"In our paper, we report on a new paradigm for lipid self-assembly leading to nanotubule formation in mixed charged systems," said Safinya.

Raviv explained, "We looked at the interaction between microtubules –– negatively charged nanometer-scale hollow cylinders derived from cell cytoskeleton –– and cationic (positively charged) lipid membranes. We discovered that, under the right conditions, spontaneous lipid protein nanotubules will form."

They used the example of water beading up or coating a car, depending on whether or not the car has been waxed. Likewise the lipid will either bead up on the surface of the microtubule, or flatten out and coat the whole cylindrical surface of the microtubule, depending on the charge.

The new type of self-assembly arises because of an extreme mismatch between the charge densities of microtubules and cationic lipid, explained Raviv. "This is a novel finding in equilibrium self-assembly," he said.

The nanotubule consisting of a three-layer wall appears to be the way the system compensates for this charge density mismatch, according to the authors.

"Very interestingly, we have found that controlling the degree of overcharging of the lipid-protein nanotube enables us to switch between two states of nanotubes," said Safinya. "With either open ends (negative overcharged), or closed ends (positive overcharged with lipid caps), these nanotubes could form the basis for controlled chemical and drug encapsulation and release."

The inner space of the nanotube in these experiments measures about 16 nanometers in diameter. (A nanometer is a billionth of a meter.) The whole capsule is about 40 nanometers in diameter.

Raviv explained that the chemotherapy drug Taxol is one type of drug that could be delivered with these nanotubes. The scientists are already using Taxol in their experiments to stabilize and lengthen the lipid-protein nanotubes.

The work was performed using state-of-the-art synchrotron x-ray scattering techniques at the Stanford Synchrotron Radiation Laboratory (SSRL), combined with sophisticated electron microscopy at UCSB. The work was funded by the National Institutes of Health and the National Science Foundation. SSRL is supported by the U.S. Department of Energy. Raviv was also supported by the International Human Frontier Science Program and the European Molecular Biology Organization.

####

Contacts:
Gail Gallessich
805-893-7220

Joan Magruder
805-893-8735

Copyright © UCSB

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

Possible Futures

A novel method for identifying the body’s ‘noisiest’ networks November 19th, 2014

Researchers discern the shapes of high-order Brownian motions November 17th, 2014

VDMA Electronics Production Equipment: Growth track for 2014 and 2015 confirmed: Business climate survey shows robust industry sector November 14th, 2014

Open Materials Development Will Be Key for HP's Success in 3D Printing: HP can make a big splash in 3D printing, but it needs to shore up technology claims and avoid the temptation of the razor/razor blade business model in order to flourish November 11th, 2014

Nanotubes/Buckyballs

Tesla NanoCoatings Increasing Use of SouthWest NanoTechnologies Carbon Nanotubes (CNTs) for its Infrastructure Coatings and Paints: High Quality SMW™ Specialty Multi-wall Carbon Nanotubes Incorporated into Teslan®-brand coatings used by Transportation, Oil and Gas Companies November 19th, 2014

Graphene/nanotube hybrid benefits flexible solar cells: Rice University labs create novel electrode for dye-sensitized cells November 17th, 2014

SouthWest NanoTechnologies to Demonstrate 3D Capacitive Touch Sensor Featuring Transparent, Thermoformed Carbon Nanotube Ink at Printed Electronics USA 2014 (Booth J25) -- “Conductive and Semiconducting Single-Wall Carbon Nanotube Inks” will be Topic of Company Presentation November 10th, 2014

Neural Canals Produced in Iran for Recovery of Sciatica Nerve November 8th, 2014

Nanomedicine

Vegetable oil ingredient key to destroying gastric disease bacteria: In mice, therapeutic nanoparticles dampen H. pylori bacteria and inflammation that lead to ulcers and gastric cancer November 25th, 2014

Research reveals how our bodies keep unwelcome visitors out of cell nuclei November 24th, 2014

ASU, IBM move ultrafast, low-cost DNA sequencing technology a step closer to reality November 24th, 2014

An Inside Job: UC-Designed Nanoparticles Infiltrate, Kill Cancer Cells From Within November 24th, 2014

Announcements

Renishaw receives Queen's Award for spectroscopy developments November 25th, 2014

JPK reports on the use of AFM and the CellHesion module to study plant cells at the University of Queensland November 25th, 2014

Vegetable oil ingredient key to destroying gastric disease bacteria: In mice, therapeutic nanoparticles dampen H. pylori bacteria and inflammation that lead to ulcers and gastric cancer November 25th, 2014

Research yields material made of single-atom layers that snap together like Legos November 25th, 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