In the world of nanotechnology, smaller is better. So if an electrode that’s a millimeter in height by a millimeter in diameter is good, then one that is 20 by 50 microns—or one-fiftieth of a millimeter by one-twentieth of a millimeter—is even better. Indeed, that’s the size of a wireless electrode developed through a collaboration between NASA’s Ames Research Center and the Mayo Clinic, a project in which Dartmouth medical alumnus Russell Andrews (MED ’78)—a neurosurgeon who has been an Ames advisor for 20 years—played an integral part. Although the technology may eventually have multiple applications, the initial concept was a tool for improved deep brain stimulation to treat symptoms of Parkinson’s disease, including tremors and slow movements.
Movement disorders such as Parkinson’s disease have been treated quite successfully by carefully placing electrodes in the brain, explains Andrews, who practices in Los Gatos, California, in addition to collaborating on research with NASA Ames and others.
Andrews has always been interested in the brain. When he first enrolled in medical school at Dartmouth, he intended to pursue neurology. However, he was inspired to become a neurosurgeon when as a first-year medical student, he “watched Dr. Donald Wilson save a toddler with a traumatic epidural hematoma—converting an almost certainly fatal situation into a joyous event for all concerned,” Andrews recalls. Later, he collaborated with Dr. Peter Spiegel, also on Dartmouth’s faculty, on a research project reviewing the clinical characteristics of patients with cerebral aneurysms, an experience that fueled his interest in research, too.
Andrews’ recent project with nanoelectrodes was inspired by another research team at NASA Ames that had developed nanoelectrodes that were ten times more sensitive than standard electrodes in measuring dopamine. Dopamine is a neurotransmitter that’s essential to the functioning of the central nervous system. Andrews instantly saw a potential application in Parkinson’s disease, which results from damage to dopamine-producing brain cells in the basal ganglia.
So with a grant from the National Institutes of Health (NIH), Andrews and colleagues at NASA Ames began developing nanoelectrodes expressly to monitor both dopamine and brain electrical activity, as well as stimulate the brain more precisely than was possible with standard electrodes. About the same time, researchers at the Mayo Clinic published information about a wireless system for monitoring neurotransmitters in human beings.
In 2011, the NASA Ames and Mayo teams came together with a five-year, nearly $2 million NIH grant that enabled them to develop a nanoelectrode that operates on a wireless Bluetooth system. Andrews says the nanoelectrode will improve doctors’ and researchers’ ability to monitor both electrical and chemical activity in the brain, and also improve the precision of deep brain stimulation.
Now that the NIH grant has ended, Andrews and his NASA Ames colleagues are continuing to develop nanotechniques to understand the basic electrochemistry of brain functioning.
“The brain is an elegant structure, with billions of cells—neurons and glia—communicating electrically and chemically at the cellular or micron level,” says Andrews. “By understanding the brain electrochemically, we are much more likely to be able to coax the disordered brain—whether it’s Parkinson’s disease, epilepsy, or depression—back to healthy functioning.”
Author: Sarah Zobel