Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Mini-beacon design a major development for smart drug delivery

Abstract:
A nanoscopic beacon used by Melbourne researchers will help to enhance the design of smart gene and drug delivery systems.

Mini-beacon design a major development for smart drug delivery

August 02, 2005

A team from the University of Melbourne’s Department of Chemical and Biomolecular Engineering has used a molecular beacon made from single DNA strands to measure how easily DNA (e.g. genes) can pass through the wall of drug delivery particles.

Federation Fellow Professor Frank Caruso, who heads the Centre for Nanoscience and Nanotechnology, says, “The past number of years has seen major advances in the design of ‘molecular vehicles’ – particles that can be filled with a medicine or new genes. The vehicles then ferry their contents to the site in the body where they are needed.”

“One of the major roadblocks that we have encountered in designing these molecular transport systems is how to get the vehicle contents out of their container once they reach the site where they are needed.”

In order to achieve this effectively, the researchers need to know how big the pores in the vehicle’s membranes are and how easily the contents can pass through them. This has proved quite difficult.

Dr. Angus Johnston who works with Professor Caruso says, “Scientists designing these drug-delivery vehicles need to be able to measure the very small number of molecules which pass through the membrane. Normally, we could label the molecules, so we can see them as they pass through. The problem with this is that adding a label alters the size, so the ability to pass through the pore will change when the label is removed.”

Dr. Johnston and Professor Caruso have developed a clever technique that overcomes this problem which allows scientists to rapidly and accurately determine the permeability of DNA through films.

The beacons the researchers used are single DNA strands which have a light-emitting molecule (a fluorophore) at one end and a quencher at the other. A fluorophore is simply a molecule that emits light and a quencher is a molecule that stops the fluorophore from emitting light.

The DNA strand self assembles so that the two end segments pair up, forming a loop in the centre – much like the shape of a round-bottomed flask. This is the closed molecular beacon.

When the beacon is closed the fluorophore on one end of the DNA strand is close to the “quencher” on the other end, which stops the fluorophore from giving off light.

To determine the permeability of the capsule, the molecular beacons are placed inside the delivery vehicle. If DNA passes through the capsule wall, the beacon opens and the fluorophore emits light. So when DNA passes through the capsule, the beacon is switched ‘on.’ If no DNA passes through the capsule, the beacon remains switched off.

The researchers used this technique with different length strands of DNA and were able to use the beacons to successfully determine whether or not the strands were able to pass through the membrane.

Professor Caruso says, “We hope to now use the technique in the design of intelligent drug-delivery systems which can transport medicine to target locations and release the contents in a controlled way.”

The research was recently published in the Journal of the American Chemical Society and highlighted in the July 15 Issue of the journal Science. This research was funded by the Australian Research Council.

####

Contact:
Elaine Mulcahy
Media Promotions Officer
emulcahy@unimelb.edu.au
Tel: 61 3 8344 0181
Mob: 0421 641 506

Frank Caruso
Chemical and Biomolecular Engineering
(03) 8344 3461
fcaruso@unimelb.edu.au

Angus Johnston
Chemical and Biomolecular Engineering
(03) 8344 9833
0409 863 255
angusj@unimelb.edu.au

Copyright © University of Melbourne

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

Self Assembly

Carnegie Mellon chemists create tiny gold nanoparticles that reflect nature's patterns April 9th, 2015

DWI scientists program the lifetime of self-assembled nanostructures April 9th, 2015

In situ production of biofunctionalised few-layer defect-free microsheets of graphene April 7th, 2015

Designer's toolkit for dynamic DNA nanomachines: Arm-waving nanorobot signals new flexibility in DNA origami March 27th, 2015

Nanomedicine

Optical resonance-based biosensors designed for medical applications April 18th, 2015

Nanocomposites Play Effective Role in Production of Smart Fibers April 18th, 2015

Novel nanoparticles could save soldiers' lives after explosions April 15th, 2015

Nanoparticles at specific temperature stimulate antitumor response: Dartmouth researchers identify precise heat to boost immune system against cancer tumors April 14th, 2015

Sensors

Optical resonance-based biosensors designed for medical applications April 18th, 2015

MIT sensor detects spoiled meat: Tiny device could be incorporated into 'smart packaging' to improve food safety April 15th, 2015

Graphene pushes the speed limit of light-to-electricity conversion: Researchers from ICFO, MIT and UC Riverside have been able to develop a graphene-based photodetector capable of converting absorbed light into an electrical voltage at ultrafast timescales April 14th, 2015

Iranian Scientists Evaluate Dynamic Interaction between 2 Carbon Nanotubes April 14th, 2015

Discoveries

How to maximize the superconducting critical temperature in a molecular superconductor: International team led by Tohoku University opens new route for discovering high Tc superconductors April 19th, 2015

Optical resonance-based biosensors designed for medical applications April 18th, 2015

Iranian Foodstuff, Agricultural Industries Welcome Nanotechnology Packaging Bags April 18th, 2015

Nanocomposites Play Effective Role in Production of Smart Fibers April 18th, 2015

Announcements

How to maximize the superconducting critical temperature in a molecular superconductor: International team led by Tohoku University opens new route for discovering high Tc superconductors April 19th, 2015

Iranian Foodstuff, Agricultural Industries Welcome Nanotechnology Packaging Bags April 18th, 2015

Nanocomposites Play Effective Role in Production of Smart Fibers April 18th, 2015

Dais Analytic Corporation Appoints Eliza Wang to Board of Directors: Company's Newest Director Brings Expertise in Commercial and Legal Matters Both in the United States and China; Joins on the Heels of Successful Business Development Trade Mission to China April 18th, 2015

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 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE