Researchers create nanotubes as small as 1/2,000,000 ants

Researchers create nanotubes that don't leak, don't clog, and could deliver drugs in the future.

The team at Johns Hopkins University's Whiting School of Engineering developed leak-free nanotubes using strands of DNA. The diameter of each nanotube is only about 7 nanometers - as small as about 1/2,000,000 million ants - and as long as a speck of dust. The new study was published in the journal Science Advances on September 7.

The nanotubes do not leak. (Image: Johns Hopkins University)

By combining nanotubes, the team of scientists was able to grow large networks and link them to many microscopic biological structures (structures in living organisms) to perform different tasks, such as biomolecule transport.

"The tiny tube system can help analyze individual molecules, which in turn helps us make better drugs or enzymes, separate toxins, and even make better batteries by designing tubes for ions pass through instead of using a porous material," explained Associate Professor Rebecca Schulman at Johns Hopkins University, a member of the research team.

The team confirmed that the new nanotubes do not leak through the tube walls and that they do not clog despite their extremely small diameter. Scientist Yi Li, a member of the research team, performed an interesting experiment to test the non-leakage of nanotubes. He filled the tube with fluorescent liquid, sealed the tip, and then observed the tube's shape change as the liquid moved inside.

As a result, leakage does not occur during the test. What's more, the new nanotubes are made of DNA, so they are also capable of self-repair and self-assembly, the team said.

Nanotubes have potential applications in drug delivery. They can be used to direct the flow of molecules or ions between cells in tissues. Such an application is important for the development of tissues in the laboratory. However, before nanotubes can be widely used, further studies, animal studies and clinical trials need to be carried out.

Schulman says his team has only studied leaks with one type of molecule - a fluorescent dye. They will need to repeat the method with other molecules to learn more about which types of molecules can be easily transported or collected. The team also said that if they wanted to transport something smaller, such as "ions", they would have to fabricate a coating for the nanotubes.