'Smart' DNA-based nanomeds self-assemble to release cancer drug

In constructing nanoparticles with the ability to deliver drugs, the way particles self-assemble plays a critical part in their ultimate effectiveness as drug vehicles. And now, chemists at Syracuse University have developed a "smart," temperature-controlled polymer that uses the DNA code to assemble itself into a structure capable of triggering the release of toxic cancer drugs.

The team of researchers created a polymer that reacts to temperature, controlling the release of the cancer drug doxorubicin. In an article in ACS Nano, the team showed that strands in the polymer shrink at high temperatures, exposing the DNA and triggering the release of the drug. At lower temperatures, the polymer blocks the DNA recognition, and the drug remains in the structure, according to a university report.

The use of DNA as a triggering mechanism pushes the technology to the cutting edge of nanomedicine. "This multipurpose functionality and added 'smart' component are indicative of where nanoscience is going," said lead researcher Mathew Maye. "We want nanomaterials to perform many tasks at once, and we want to be able to turn their interactions on and off remotely."

And because of this precise control, the toxicity of the drug can be increased sixfold, according to the report, bringing more of the drug to cancer cells and less of it to healthy cells, cutting down on the side effects.

"Being able to control nanoparticle assembly with temperature allows us to fine-tune their reactions and form more predictable structures. It also gives us a more improved system in which to scale assembly," Maye said. "When combined with thermosensitive polymers such as the ones in our system, they could become very lucrative."

- here's the Syracuse University report
- and the research abstract