Nanostructures made of DNA strands can encapsulate, release small-molecule drugs

September 1, 2013
A DNA cage (at left), with lipid-like molecules (in blue). The lipids come together in a "handshake" within the cage (center image) to encapsulate small-molecule drugs (purple). The molecules are released (at right) in response to the presence of a specific nucleic acid. Credit: Thomas Edwardson, McGill University

Nanoscale "cages" made from strands of DNA can encapsulate small-molecule drugs and release them in response to a specific stimulus, McGill University researchers report in a new study.

The research, published online Sept. 1 in Nature Chemistry, marks a step toward the use of biological nanostructures to deliver drugs to diseased cells in patients. The findings could also open up new possibilities for designing DNA-based nanomaterials.

"This research is important for drug delivery, but also for fundamental and nanotechnology," says McGill Chemistry professor Hanadi Sleiman, who led the research team.

DNA carries the genetic information of all from one generation to the next. But strands of the material can also be used to build nanometre-scale structures. (A nanometre is one billionth of a metre – roughly one-100,000th the diameter of a human hair.)

In their experiments, the McGill researchers first created DNA cubes using short DNA strands, and modified them with lipid-like molecules. The lipids can act like sticky patches that come together and engage in a "handshake" inside the DNA cube, creating a core that can hold cargo such as .

The McGill researchers also found that when the sticky patches were placed on one of the outside faces of the DNA cubes, two cubes could attach together. This new mode of assembly has similarities to the way that proteins fold into their functional structures, Sleiman notes. "It opens up a range of new possibilities for designing DNA-based nanomaterials."

Sleiman's lab has previously demonstrated that can be loaded and released from DNA nanotubes, providing a preliminary that drug delivery might be possible. But the new study marks the first time that small molecules—which are considerably smaller than the gold nanoparticles—have been manipulated in such a way using a DNA nanostructure, the researchers report.

DNA nanostructures have several potential advantages over the synthetic materials often used to deliver drugs within the body, says Thomas Edwardson, a McGill doctoral student and co-author of the new paper. "DNA structures can be built with great precision, they are biodegradable and their size, shape and properties can be easily tuned".

The DNA cages can be made to release drugs in the presence of a specific nucleic acid sequence. "Many , such as cancer cells, overexpress certain genes," Edwardson adds. "In a future application, one can imagine a DNA cube that carries drug cargo to the diseased cell environment, which will trigger the release of the drug." The Sleiman group is now conducting cell and animal studies to assess the viability of this method on chronic lymphocytic leukemia (CLL) and prostate cancer, in collaboration with researchers at the Lady Davis Institute for Medical Research at Montreal's Jewish General Hospital.

Explore further: DNA 'tricked' to act as nano-building blocks

More information: Site-specific positioning of dendritic alkyl chains on DNA cages enables their geometry-dependent self-assembly, DOI: 10.1038/nchem.1745

Related Stories

DNA 'tricked' to act as nano-building blocks

April 13, 2009

( -- McGill researchers have succeeded in finding a new way to manufacture nanotubes, one of the important building blocks of the nanotechnology of the future. Their building material? Biological DNA.

Stiffening the backbone of DNA nanofibers

July 24, 2013

An international collaboration including researchers from the NIST Center for Nanoscale Science and Technology and the Universidad San Francisco de Quito, Ecuador have fabricated a self-assembled nanofiber from a DNA building ...

Recommended for you

Building a better liposome

October 13, 2015

Using computational modeling, researchers at Carnegie Mellon University, the Colorado School of Mines and the University of California, Davis have come up with a design for a better liposome. Their findings, while theoretical, ...

Dielectric film has refractive index close to air

October 12, 2015

Researchers from North Carolina State University have developed a dielectric film that has optical and electrical properties similar to air, but is strong enough to be incorporated into electronic and photonic devices - making ...

Have your drug nano-delivered via microbubble

October 12, 2015

"Colloidal delivery system" and "nanoparticle" are probably not terms you find yourself using in day-to-day interactions, but for UC's Yoonjee Park, assistant professor in the College of Engineering and Applied Science biomedical ...


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.