Tiny Spheres with Different Faces: Targeted Drug Delivery

 
Post new topic   Reply to topic    Institute of Nanotechnology Forum Index -> Nanobiomed
View previous topic :: View next topic  
Author Message
nanoorg
Site Admin


Joined: 16 Mar 2004
Posts: 1392

PostPosted: Fri Sep 05, 2008 3:47 pm    Post subject: Tiny Spheres with Different Faces: Targeted Drug Delivery Reply with quote

Tiny Spheres with Different Faces Can be Used as Shuttles, Self Propelled Sensors and Targeted Drug Delivery Devices
For the first time, researchers at North Carolina State University have demonstrated that microscopic "two-faced" spheres whose halves are physically or chemically different so-called Janus particles will move like stealthy submarines when an alternating electrical field is applied to liquid surrounding the particles.
A paper describing the research, published in the Feb. 8, 2008, edition of Physical Review Letters, advances knowledge about how potential "smart" materials think of tiny engines or sensors can move around and respond to changes in their environment. Janus particles could be used as microscopic mixers, molecular "shuttles," self-propelling microsensors or means of targeted drug delivery.

The researchers Dr. Orlin Velev, associate professor of chemical and biomolecular engineering at NC State and lead author of the paper; Sumit Gangwal, an NC State graduate student; Dr. Olivier Cayre, a post-doctoral researcher in Velev's lab; and Dr. Martin Bazant from Massachusetts Institute of Technology created tiny two-faced gold and plastic particles and applied low frequency alternating current to the water containing the particles. The electric field was of voltage and frequency similar to the ones you'd get if you plugged a device into a socket in your home or office.



North Carolina State University research demonstrated "two-faced," micrometer-sized particles that propelled themselves perpendicular to the direction of an electrical field,
not in the direction of the field, as would be expected.

Velev says the micrometer-sized particles convert the electrical field into liquid motion around them and then unexpectedly propel themselves perpendicular to the direction of the powered electrodes
not in the direction of the electrical field, as would be expected. The particles always travel in the same orientation: with the plastic "face" as the front of the mini-submarine and the metallic "face" in the rear, Velev added.

The phenomenon called "induced-charge electrophoresis," which had been predicted in a theoretical model by the MIT collaborator had not been demonstrated previously.

The term "Janus particle" comes from the name of a Roman god with two faces. Velev says that these materials have the potential to perform a variety of applications.

"You can imagine other types of Janus particles comprising a 'smart gel' that responds to a change in its environment and then releases drugs, for example," Velev says. Fabricating these responsive materials on the microscale and nanoscale is an exciting and rapidly developing area of science, he adds.

"We are able to create tiny Janus particles of the same size and shape and are beginning to learn how to give them functionality," Velev said. "The next step is to create more complex particles that are able to perform more specialized functions in addition to propelling themselves around."
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    Institute of Nanotechnology Forum Index -> Nanobiomed All times are GMT
Page 1 of 1
 

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2002 phpBB Group