


14 June 2013

Researchers have created 'nano-volcanoes' that are able to store precise amounts of other materials making them ideal candidates for drug-delivery.

Cross-section of a nano-volcano carved using light (image: Chih-Hao Chang)

The nano-volcanoes, created by shining various colours of light through a nanoscale 'crystal ball' made of a synthetic polymer, can store precise amounts of other materials and hold promise for new drug-delivery technologies.

The researchers, from North Carolina (UC) State University, create the nano-volcanoes by placing spherical, transparent polymer nanoparticles directly onto the flat surface of a thin film. They then shine ultraviolet light through the transparent sphere, which scatters the light and creates a pattern on the thin film.

The thin film is made of a photo-reactive material that undergoes a chemical change wherever it has been struck by the light. The researchers then submerge the thin film in a liquid solution that washes away the parts of the film that were exposed to light. The material that remains is shaped like a nanoscale volcano.

"We can control the pattern of light by changing the diameter of the nanoparticle spheres, or by changing the wavelength of the light that we shine through the spheres," says Xu Zhang, a doctoral student in mechanical and aerospace engineering at NC State and lead author of a paper describing the work.



Because these structures have precisely measured hollow cores, and precisely measured openings at the "mouth" of the nano-volcanoes, they are good candidates for drug-delivery mechanisms.


"The materials used in this process are relatively inexpensive, and the process can be easily scaled up," says Dr Chih-Hao Chang, an assistant professor of mechanical and aerospace engineering at NC State and co-author of the paper. "In addition, we can produce the nano-volcanoes in a uniformly patterned array, which may also be useful for controlling drug delivery."

Chang's team is now working to improve its understanding of the release rate from the nano-volcanoes, such as how quickly nanoparticles of different sizes will "escape" from nano-volcanoes with different-sized mouths. "That's essential information for drug-delivery applications," Chang says.


Print this page | E-mail this page

Drives and Controls 2020