(Press-News.org) Researchers from North Carolina State University have developed a method for creating "nano-volcanoes" by shining various colors of light through a nanoscale "crystal ball" made of a synthetic polymer. These nano-volcanoes can store precise amounts of other materials and hold promise for new drug-delivery technologies.
The researchers 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 photoreactive 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 – or color – 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. "That means we can control the shape and geometry of these structures, such as how big the cavity of the nano-volcano will be."
The researchers developed a highly accurate computer model that predicts the shape and dimensions of the nano-volcanoes based on the diameter of the nanoscale sphere and the wavelength of light.
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 size of the core would allow users to control the amount of the drug a nano-volcano would store, while the size of the opening at the top of the nano-volcano could be used to regulate the drug's release.
"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.
"It's exciting to take our understanding of how light scatters by particles and apply it to nanolithography in order to come up with something that could actually help people."
INFORMATION:
The paper, "Three-Dimensional Nanolithography Using Light Scattering from Colloidal Particles," was published online June 12 in ACS Nano. Lead author of the paper is NC State Ph.D. student Xu Zhang. Co-authors are Chang and NC State master's student Jonathan Elek. The research was supported by a NASA Early Career Faculty Award and the National Science Foundation's ASSIST Engineering Research Center at NC State.
Light-carved 'nano-volcanoes' hold promise for drug delivery
2013-06-13
ELSE PRESS RELEASES FROM THIS DATE:
DNA brings materials to life
2013-06-13
A colloid is a substance spread out evenly inside another substance. Everyday examples include milk, styrofoam, hair sprays, paints, shaving foam, gels and even dust, mud and fog. One of the most interesting properties of colloids is their ability to self-assemble – to aggregate spontaneously into well-defined structures, driven by nothing but local interactions between the colloid's particles. Self-assembly has been of major interest in industry, since controlling it would open up a whole host of new technologies, such as smart drug-delivery patches or novel paints that ...
DNA sequencing uncovers secrets of white cliffs of Dover
2013-06-13
The University of Exeter recently contributed to a major international project to sequence the genome of Emiliania huxleyi, the microscopic plankton species whose chalky skeletons form the iconic white cliffs of Dover. The results of the project are published this week in the journal Nature.
Emiliania huxleyi is one of the most abundant marine phytoplankton species and is a key player in the process of CO2 exchange between the atmosphere and the ocean. In some marine systems 20% of the total carbon is fixed by E. huxleyi. This microscopic alga has influenced the global ...
UF study finds brain-imaging technique can help diagnose movement disorders
2013-06-13
GAINESVILLE, Fla. — A new University of Florida study suggests a promising brain-imaging technique has the potential to improve diagnoses for the millions of people with movement disorders such as Parkinson's disease.
Utilizing the diffusion tensor imaging technique, as it is known, could allow clinicians to assess people earlier, leading to improved treatment interventions and therapies for patients.
The three-year study looked at 72 patients, each with a clinically defined movement disorder diagnosis. Using a technique called diffusion tensor imaging, the researchers ...
Gene offers an athlete's heart without the exercise
2013-06-13
Researchers at Case Western Reserve University have found that a single gene poses a double threat to disease: Not only does it inhibit the growth and spread of breast tumors, but it also makes hearts healthier.
In 2012, medical school researchers discovered the suppressive effects of the gene HEXIM1 on breast cancer in mouse models. Now they have demonstrated that it also enhances the number and density of blood vessels in the heart – a sure sign of cardiac fitness.
Scientists re-expressed the HEXIM1 gene in the adult mouse heart and found that the hearts grew heavier ...
Study points to role of nervous system in arthritis
2013-06-13
Arthritis is a debilitating disorder affecting one in 10 Canadians, with pain caused by inflammation and damage to joints.
Yet the condition is poorly managed in most patients, since adequate treatments are lacking – and the therapies that do exist to ease arthritis pain often cause serious side effects, particularly when used long-term. Any hope for developing more-effective treatments for arthritis relies on understanding the processes driving this condition.
A new study in the Journal of Neuroscience by researchers at McGill University adds to a growing body of ...
A peptide to protect brain function
2013-06-13
A structure called "the microtubule network" is a crucial part of our nervous system. It acts as a transportation system within nerve cells, carrying essential proteins and enabling cell-to-cell communications. But in neurodegenerative diseases like Alzheimer's, ALS, and Parkinson's, this network breaks down, hindering motor abilities and cognitive function.
Now Prof. Illana Gozes of Tel Aviv University's Sackler Faculty of Medicine has developed a new peptide in her lab, called NAP or Davunetide, that has the capacity to both protect and restore microtubule function. ...
Helping to restore balance after inner ear disorder
2013-06-13
Many disorders of the inner hear which affect both hearing and balance can be hugely debilitating and are currently largely incurable. Cochlear implants have been used for many years to replace lost hearing resulting from inner ear damage. However, to date, there has not been an analogous treatment for balance disorders resulting from inner ear disease. One potential new treatment is an implantable vestibular prosthesis which would directly activate the vestibular nerve by electrical stimulation. This prosthetic treatment is tested in a new study by Christopher Phillips ...
US forest management policy must evolve to meet bioenergy targets
2013-06-13
CHAMPAIGN, Ill. — In order to keep pace with the burgeoning demand for renewable energy, forest management policy in the U.S. must change to address environmental sustainability issues, according to an article by a University of Illinois expert in bioenergy law.
Unless the forestry sector can tailor sustainable forest management policies specifically to forest-to-energy feedstocks, its role in helping the country broaden its energy portfolio – and by extension, meeting ambitious bioenergy targets – may be limited in large part because of uncertainty about whether existing ...
No good substitute for race in college admissions: Research
2013-06-13
COLLEGE PARK, Md. – As the U.S. Supreme Court decides in a case involving racial preferences in higher education admissions (Fisher v. Texas), new University of Maryland-led research finds that socioeconomic diversity is no replacement for a direct consideration of race, as some have suggested. Still the research finds that a mix of students from differing socio-economic backgrounds has benefits.
The peer-reviewed study appears in the June issue of the "American Educational Research Journal." It evaluates the use of "socio-economic status" as a racially blind way to build ...
Yale researchers unravel genetics of dyslexia and language impairment
2013-06-13
A new study of the genetic origins of dyslexia and other learning disabilities could allow for earlier diagnoses and more successful interventions, according to researchers at Yale School of Medicine. Many students now are not diagnosed until high school, at which point treatments are less effective.
The study is published online and in the July print issue of the American Journal of Human Genetics. Senior author Jeffrey R. Gruen, M.D., professor of pediatrics, genetics, and investigative medicine at Yale, and colleagues analyzed data from more than 10,000 children born ...