Zhao Zhao, Erica Jacovetty, Yan Liu, and Hao Yan have demonstrated the ability to create a rectangular box with a cavity using the self assembly properties of DNA origami. This structure exhibits a relatively high folding yield and was also found to be robust enough to survive in a variety of environments. Aside from this particular stricture, DNA origami has a number of inherent advantages over other types of nanoparticles used for similar drug delivery applications. Currently there exists no equivalent technology capable of making a seemingly infinite number of arbitrary shapes like one can with DNA nanotechnology. Another chief advantage is the ease with which the surface of these structures can be functionalized simply by extending oligonucleotides. Functional polymers can be synthesized and then attached to the extended ends. Not only are these structures easy to functionalize, but the number of functional groups that can be attached is limited only by the number of extended oligos, which in our case is on the order of ~100.
With an increasing number of neurological questions still requiring answers, one prominent barrier that remains is a difficulty transporting drugs across the blood-brain-barrier. Creating a vehicle capable of delivering drugs to the brain, concentrating the biodistribution almost entirely to the brain, would be an extremely valuable tool towards advancing treatment for neurological diseases. Additionally, it still is very difficult to study neuronal activity in the brains of monkeys and humans. When working with mice and rats, there exists a wide variety of recording equipment that can be inserted in the brain with ease. IF these particles can be delivered to the brain with ease, they can also be packaged with entities that can record or stimulate neurons.
The aim of our project is to develop a general strategy to functionalize DNA structures with bioactive cues, namely peptides.
We will demonstrate the utility of this approach with two applications. First, we will attempt to get structures into cells in an organized and controlled fashion, and second, get structures to pass through the blood-brain-barrier and enter the brain through the bloodstream.
Our approach first involves modifying the ends of an existing box structure with a cavity.
Oligonucleotides are extended from the two ends of the box perpendicular to the plane of the cavity.
Once the crude folded structure has been purified to remove stables and misfolded structures, a synthesized carrier polymer can be attached to a complimentary capping sequence that will bind to the extended ends to create functional sites at each extended helix.
1. Modify the original literature box with extended ends.
2. Cap the extended ends with a fluorophore to verify functionalization capabilty.
3. Make the polymer for functionalization and verify binding.
3. Scale up products.4. Test in cells and mice and compare to control.