Gold nanoparticles for controlled drug delivery

December 30, 2008
The top image shows a mixture of gold nanoparticles. The longer particles are called nanobones, and the smaller are nanocapsules. Bottom left: After the nanoparticles are hit with 800 nanometer wavelength infrared light, the nanocapsules melt and release their payload. Nanobones remain intact. Right: After the nanoparticles are hit with 1100 nanometer wavelength infrared light, the nanobones melt and release their payload. Nanocapsules remain intact. Image: Andy Wijaya

(PhysOrg.com) -- Using tiny gold particles and infrared light, MIT researchers have developed a drug-delivery system that allows multiple drugs to be released in a controlled fashion.

Such a system could one day be used to provide more control when battling diseases commonly treated with more than one drug, according to the researchers.

"With a lot of diseases, especially cancer and AIDS, you get a synergistic effect with more than one drug," said Kimberly Hamad-Schifferli, assistant professor of biological and mechanical engineering and senior author of a paper on the work that recently appeared in the journal ACS Nano.

Delivery devices already exist that can release two drugs, but the timing of the release must be built into the device — it cannot be controlled from outside the body. The new system is controlled externally and theoretically could deliver up to three or four drugs.

The new technique takes advantage of the fact that when gold nanoparticles are exposed to infrared light, they melt and release drug payloads attached to their surfaces.

Nanoparticles of different shapes respond to different infrared wavelengths, so "just by controlling the infrared wavelength, we can choose the release time" for each drug, said Andy Wijaya, graduate student in chemical engineering and lead author of the paper.

The team built two different shapes of nanoparticles, which they call "nanobones" and "nanocapsules." Nanobones melt at light wavelengths of 1,100 nanometers, and nanocapsules at 800 nanometers.

In the ACS Nano study, the researchers tested the particles with a payload of DNA. Each nanoparticle can carry hundreds of strands of DNA, and could also be engineered to transport other types of drugs.

In theory, up to four different-shaped particles could be developed, each releasing its payload at different wavelengths.

Provided by Massachusetts Institute of Technology

Explore further: A safe optical fiber for delivering light and drugs into the body

Related Stories

Novel thermal ablation system for transdermal drug delivery

July 27, 2017

Many diseases are treated with protein-based drugs. However, due to the size of the molecules, the only effective delivery method is through injection, which can suffer from low patient compliance. Furthermore, many of these ...

Recommended for you

Breakthrough in ultra-fast data processing at nanoscale

October 20, 2017

A research team from the National University of Singapore has recently invented a novel "converter" that can harness the speed and small size of plasmons for high frequency data processing and transmission in nanoelectronics.

Art advancing science at the nanoscale

October 18, 2017

Like many other scientists, Don Ingber, M.D., Ph.D., the Founding Director of the Wyss Institute, is concerned that non-scientists have become skeptical and even fearful of his field at a time when technology can offer solutions ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.