Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



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

Liquid crystal templated chiral nanomaterials October 14th, 2022

Nanoclusters self-organize into centimeter-scale hierarchical assemblies April 22nd, 2022

Atom by atom: building precise smaller nanoparticles with templates March 4th, 2022

Nanostructures get complex with electron equivalents: Nanoparticles of two different sizes break away from symmetrical designs January 14th, 2022

Nanomedicine

High-tech 'paint' could spare patients repeated surgeries March 8th, 2024

Researchers develop artificial building blocks of life March 8th, 2024

Curcumin nanoemulsion is tested for treatment of intestinal inflammation: A formulation developed by Brazilian researchers proved effective in tests involving mice March 8th, 2024

The Access to Advanced Health Institute receives up to $12.7 million to develop novel nanoalum adjuvant formulation for better protection against tuberculosis and pandemic influenza March 8th, 2024

Sensors

$900,000 awarded to optimize graphene energy harvesting devices: The WoodNext Foundation's commitment to U of A physicist Paul Thibado will be used to develop sensor systems compatible with six different power sources January 12th, 2024

A color-based sensor to emulate skin's sensitivity: In a step toward more autonomous soft robots and wearable technologies, EPFL researchers have created a device that uses color to simultaneously sense multiple mechanical and temperature stimuli December 8th, 2023

New tools will help study quantum chemistry aboard the International Space Station: Rochester Professor Nicholas Bigelow helped develop experiments conducted at NASA’s Cold Atom Lab to probe the fundamental nature of the world around us November 17th, 2023

TU Delft researchers discover new ultra strong material for microchip sensors: A material that doesn't just rival the strength of diamonds and graphene, but boasts a yield strength 10 times greater than Kevlar, renowned for its use in bulletproof vests November 3rd, 2023

Discoveries

What heat can tell us about battery chemistry: using the Peltier effect to study lithium-ion cells March 8th, 2024

Researchers’ approach may protect quantum computers from attacks March 8th, 2024

High-tech 'paint' could spare patients repeated surgeries March 8th, 2024

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

Announcements

What heat can tell us about battery chemistry: using the Peltier effect to study lithium-ion cells March 8th, 2024

Curcumin nanoemulsion is tested for treatment of intestinal inflammation: A formulation developed by Brazilian researchers proved effective in tests involving mice March 8th, 2024

The Access to Advanced Health Institute receives up to $12.7 million to develop novel nanoalum adjuvant formulation for better protection against tuberculosis and pandemic influenza March 8th, 2024

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

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




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project