Research finds gallium nitride is non-toxic, biocompatible - holds promise for implants

Oct 24, 2011
This is a scanning electron microscope image of cell growth on GaN that has been coated with peptides. Credit: Albena Ivanisevic, North Carolina State University

Researchers from North Carolina State University and Purdue University have shown that the semiconductor material gallium nitride (GaN) is non-toxic and is compatible with human cells – opening the door to the material's use in a variety of biomedical implant technologies.

GaN is currently used in a host of technologies, from LED lighting to optic sensors, but it is not in widespread use in biomedical implants. However, the new findings from NC State and Purdue mean that GaN holds promise for an array of implantable technologies – from electrodes used in neurostimulation therapies for Alzheimer's to transistors used to monitor blood chemistry.

"The first finding is that GaN, unlike other semiconductor materials that have been considered for biomedical implants, is not toxic. That minimizes risk to both the environment and to patients," says Dr. Albena Ivanisevic, who co-authored a paper describing the research. Ivanisevic is an associate professor of materials science and engineering at NC State and associate professor of the joint biomedical engineering program at NC State and the University of North Carolina at Chapel Hill.

Researchers used a mass spectrometry technique to see how much gallium is released from GaN when the material is exposed to various environments that mimic conditions in the human body. This is important because gallium oxides are toxic. But the researchers found that GaN is very stable in these environments – releasing such a tiny amount of gallium that it is non-toxic.

The researchers also wanted to determine GaN's potential biocompatibility. To do this they bonded peptides – the building blocks that make up proteins – to the GaN material. Researchers then placed peptide-coated GaN and uncoated GaN into cell cultures to see how the material and the interacted.

Researchers found that the peptide-coated GaN bonded more effectively with the cells. Specifically, more cells bonded to the material and those cells spread over a larger area.

"This matters because we want that give us some control over cell behavior," Ivanisevic says. "For example, being able to make cells adhere to a material or to avoid it.

"One problem facing many , such as sensors, is that they can become coated with biological material in the body. We've shown that we can coat GaN with peptides that attract and bond with cells. That suggests that we may also be able to coat GaN with peptides that would help prevent cell growth – and keep the implant 'clean.' Our next step will be to explore the use of such 'anti-fouling' peptides with GaN."

Explore further: Novel microscopy pencils patterns in polymers at the nanoscale

More information: "Gallium Nitride is Biocompatible and Non-Toxic Before and After Functionalization with Peptides," forthcoming paper in Acta Biomaterialia.

Related Stories

Cancer detection from an implantable, flexible LED

Sep 19, 2011

Can a flexible LED conformably placed on the human heart, situated on the corrugated surface of the human brain, or rolled upon the blood vessels, diagnose or even treat various diseases? These things might ...

NXP brings GaN technology mainstream

Jun 07, 2011

At IMS2011 this week, NXP Semiconductors N.V. is showcasing a live demo of its next-generation products based on Gallium Nitride (GaN) technology.

Recommended for you

Self-repairing subsea material

Dec 16, 2014

Embryonic faults in subsea high voltage installations are difficult to detect and very expensive to repair. Researchers believe that self-repairing materials could be the answer.

User comments : 3

Adjust slider to filter visible comments by rank

Display comments: newest first

Standing Bear
not rated yet Oct 24, 2011
Ahhh, the zombie creation mechanism to create remote controlled people....bond to brain cells. Make insectlike soldiers. Soul-less police. Totalitarian governments will LOVE this! May God have mercy on us all!
Mabus
1 / 5 (3) Oct 24, 2011
So in the future we might see people covered entirely in LED implants that light red when get angry?
Cave_Man
1 / 5 (1) Oct 24, 2011
I prefer to imagine a super cooled boot made of gallium nitride that would allow me to use earths intense magnetic field to fly.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.