Nav: Home

New silicon structures could make better biointerfaces

August 01, 2016

A team of researchers from the University of Chicago, Northwestern University, the University of Illinois at Chicago and the U.S. Department of Energy's (DOE) Argonne National Laboratory have engineered silicon particles one-fiftieth the width of a human hair, which could lead to "biointerface" systems designed to make nerve cells fire and heart cells beat.

Bozhi Tian, who led one of the University of Chicago research groups, said the particles can establish unique biointerfaces on cell membranes, because they are deformable but can still yield a local electrical effect.

"Biological systems are soft, and if you want to design a device that can target those tissues or organs, you should match their mechanical interface as well," Tian said. "Most of the current implants are rigid, and that's one of the reasons they can cause inflammation."

Over time biointerfaces made out of these particles will also degrade, unlike alternative materials like gold and carbon, said study co-author Yuanwen Jiang, a graduate student in the Tian group. This means that for future applications patients wouldn't have to undergo a second procedure to have the particles removed.

Jiang and Tian said they believe the material has many potential applications in biomedicine, because the particles and light can be used to excite many types of cells.

The mesostructured silicon, named for its complex internal structures of nanoscopic wires, was created using a process called nano-casting.

To make the particles, each between one and five micrometers in size, researchers filled the beehive structure of synthetic silicon dioxide with semiconductive silicon the same way a blacksmith would pour molten metal into a cast iron mold. The outer mold was then etched away with acid, leaving behind a bundle of wires connected by thin bridges.

In order to test whether the particles could change the behavior of cells, the team injected a sample onto cultured rat dorsal root ganglia neurons, which are found in the peripheral nervous system.

The team was able to activate the neurons using pulses of light to heat up the silicon particles, causing current to flow through the cells.

In conventional biointerfaces, materials must be hooked up to a source of energy, but because researchers need only apply light to use the silicon particles, the new system is entirely wireless. Researchers can simply inject the particles in the right area and activate them through the skin.

"Neuromodulation could take full advantage of this material, including its optical, mechanical and thermal properties," Jiang said.

Along with the implications that controlling neurons might have with neurodegenerative disorders, researchers in Tian's lab have used similar materials to control the beating of heart cells, he said.

The paper's authors used resources from the Argonne X-ray Science and Chemical Sciences and Engineering Divisions and the Center for Nanoscale Materials, a DOE Office of Science User Facility.

Researchers used the 12-ID-B and 32-ID beamlines at the Advanced Photon Source, also a DOE Office of Science User Facility, to take X-ray scattering measurements, as well as transmission X-ray microscopy nano-computed tomography of the samples, scanning electron microscopy and transmission electron microscopy. The Center for Nanoscale Materials provided focused ion beam lithography instrument and expertise as well as tools for fabrication of the optical masks.

The paper was published online by Nature Materials on June 27, under the title "Heterogeneous silicon mesostructures for lipid-supported bioelectric interfaces." Argonne co-authors included Il Woong Jung, Di-Jia Liu, Xiaobing Zuo, Vincent De Andrade and Xianghui Xiao.
-end-
This work was funded by the Air Force Office of Scientific Research, the National Science Foundation, the Searle Scholars Foundation, the National Institutes of Health and the University of Chicago Start-up Fund.

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation's first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America's scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy's Office of Science.

The U.S. Department of Energy's Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit the Office of Science website.

DOE/Argonne National Laboratory

Related Neurons Articles:

New tool to identify and control neurons
One of the big challenges in the Neuroscience field is to understand how connections and communications trigger our behavior.
Neurons that regenerate, neurons that die
In a new study published in Neuron, investigators report on a transcription factor that they have found that can help certain neurons regenerate, while simultaneously killing others.
How neurons use crowdsourcing to make decisions
When many individual neurons collect data, how do they reach a unanimous decision?
Neurons can learn temporal patterns
Individual neurons can learn not only single responses to a particular signal, but also a series of reactions at precisely timed intervals.
A turbo engine for tracing neurons
Putting a turbo engine into an old car gives it an entirely new life -- suddenly it can go further, faster.
Brain neurons help keep track of time
Turning the theory of how the human brain perceives time on its head, a novel analysis in mice reveals that dopamine neuron activity plays a key role in judgment of time, slowing down the internal clock.
During infancy, neurons are still finding their places
Researchers have identified a large population of previously unrecognized young neurons that migrate in the human brain during the first few months of life, contributing to the expansion of the frontal lobe, a region important for social behavior and executive function.
How many types of neurons are there in the brain?
For decades, scientists have struggled to develop a comprehensive census of cell types in the brain.
Molecular body guards for neurons
In the brain, patterns of neural activity are perfectly balanced.
Engineering researchers use laser to 'weld' neurons
University of Alberta researchers have developed a method of connecting neurons, using ultrashort laser pulses -- a breakthrough technique that opens the door to new medical research and treatment opportunities.

Related Neurons Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Anthropomorphic
Do animals grieve? Do they have language or consciousness? For a long time, scientists resisted the urge to look for human qualities in animals. This hour, TED speakers explore how that is changing. Guests include biological anthropologist Barbara King, dolphin researcher Denise Herzing, primatologist Frans de Waal, and ecologist Carl Safina.
Now Playing: Science for the People

#SB2 2019 Science Birthday Minisode: Mary Golda Ross
Our second annual Science Birthday is here, and this year we celebrate the wonderful Mary Golda Ross, born 9 August 1908. She died in 2008 at age 99, but left a lasting mark on the science of rocketry and space exploration as an early woman in engineering, and one of the first Native Americans in engineering. Join Rachelle and Bethany for this very special birthday minisode celebrating Mary and her achievements. Thanks to our Patreons who make this show possible! Read more about Mary G. Ross: Interview with Mary Ross on Lash Publications International, by Laurel Sheppard Meet Mary Golda...