Drug Delivery Structures Built from DNA – Part of the Process for Curing Diseases
(Images courtesy of McGill University, and provided with press releases.)
Nanoscale work is incredible and some of its uses will save lives. Above are images of two nanoscale drug delivery devices created by a McGill University team led Hanadi Sleiman. The "old" version from 2010 is on the left, and is sized for delivering tiny scale items using gold nanoparticles. The "new and improved" 2013 version is on the right, and is even better because it can trap and hold "small molecules." Small molecules are even smaller than the
Both versions are literally built from DNA. The new and improved version is even smaller and uses lipids to hold DNA strands together to create the cage. In turn, the cage can hold a tiny amount of a substance that may, upon release, block the action of a protein. Blocking a protein will matter significantly when that protein is part of the chain of events by which cancers grow rapidly. The cage also is impressive because it can be set so that it will open when it finds a specific protein, such as a protein generated by a particular type of cancer cell.
Set out below is background from ScienceDaily’s article from the McGill press release with more of the specifics about the scale and structure of the new and improved version:
"DNA carries the genetic information of all living organisms 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 drug molecules.
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 gold nanoparticles can be loaded and released from DNA nanotubes, providing a preliminary proof of concept 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."