Remote Controlled Drug Release

A team of researchers at MIT, initially designing nanoparticles that would accumulate at tumors and aid in MRI imaging, have devised "remote controlled" nanoparticles. The nanoparticles enter the blood stream and can be activated by exterior magnetic fields; which would help in locally targeting an area for drug release.

The nanoparticles are composed of an iron oxide core, a DNA strand, and a ligated drug of interest. The iron oxide cores are superparamagnetic, which means they release incredible amounts of heat under magnetic stimulation. A double stranded DNA helix is attached to the iron oxide core, and a drug is ligated to the DNA. The heat given off by the iron oxide core under magnetic stimulation creates enough heat to denature the DNA, thereby releasing the drug of interest. By using different lengths of DNA ligated to the iron oxide core, the team can choose which iron oxide cores they want to stimulate, and therefore they can choose which drugs to release.

This new drug delivery method shows a lot of potential for cancer treatments, and would allow chemo drugs to target tumor cells specifically. The nanoparticles cannot penetrate the blood brain barrier, or the blood testes barrier, however, so they would not be useful for brain or testicular cancer.

The article can be found at

http://www.photonics.com/content/news/2007/November/20/89754.aspx?utm_s