DNA Molecule-Made Nanostructures to Become Cargo Carriers

Nanotech

A team of researchers from the University of Jyväskylä and Aalto University in Finland constructed a customized DNA nanostructure capable of executing a predefined task in body conditions similar to that of humans / Photo by: Planet99 via Wikimedia Commons

 

Nanostructures built from DNA molecules can be modified to serve as pH-responsive cargo carriers, according to a new collaborative study, which opens the gates toward practical drug-delivery vehicles.

A team of researchers from the University of Jyväskylä and Aalto University in Finland constructed a customized DNA nanostructure capable of executing a predefined task in body conditions similar to that of humans.

Science Daily reports that the team built a capsule-like carrier that opens and closes according to the pH level that surrounds the solution. It adds that the nanocapsule can then be packed with an assortment of cargo, closed to be sent out for delivery, and opened again through a subtle increase in pH.

This shows that the DNA nanocapsule's function relies on the residue of pH-responsive DNA. The report says simple hydrogen-bonding of two complementary DNA sequences often takes control of this kind of potent DNA nano design.

In the study, the scientists put specific double-stranded DNA domains in one-half of the capsule These domains could further develop a DNA triple helix—a helical structure made up of three DNA molecules—by clinging on a sitting single-stranded DNA equipped on the capsule's other half.

The formation of the triplex can only occur when the surrounding pH of the solution is "right," said Heini Ijäs, the first author of the study. Ijäs added that these pH-responsive strands are called "pH latches" since their function is similar to that of their macroscopic counterparts, locking the capsule in a closed state.

"We included multiple motifs into our capsule design to facilitate the capsule opening/closing based on [the] cooperative behavior of the latches," explained the first author, who is also a doctoral student from the Nanoscience Center at the University of Jyväskylä. "The opening of the capsule is actually very rapid and requires only a slight pH increase in the solution."