The engineers at the University of California, Berkeley have created the very first dust-sized wireless sensors that may be implanted within the body. These sensors will help to detect various deficiencies and damages in the nerves. This is bringing technology closer to the day that technologies such as the Fitbit will be able to monitor internal nerves, muscles and organs all in real time.
These devices do not require batteries and may also be able to stimulate nerves and muscles opening up doors for electroceuticals to treat disorders including epilepsy and stimulate the immune system or lower inflammation.
The neural dust is implanted in the muscles and peripheral nerves of rats and is unique due to its use of ultrasound. It holds the ability to both power and read measurements. Ultrasound technology is already very thoroughly developed for the care of hospice patients and ultrasound vibrations are able to penetrate just about everywhere within the human body making them much more useful than radio waves.
Michel Maharbiz, associate professor of electrical engineering and computer sciences is one of the main two authors of the study, says that he believes that long term prospects for neural dust are not only within nerves and the brain but much broader. Having access to telemetry within the body has never been possible because there has been no way to put something so tiny so deep. But now he can take a speck of nothing and park it next to a nerve or organ, your GI tract or a muscle, and read out the data.
The complete findings have been published in the upcoming Neuron Journal. Sensors at this time have already been shrunken to a size of 1 millimeter cube, which is about the size of a large grain of sand. These hold a piezoelectric crystal that converts ultrasound vibrations from outside of the body into electricity that powers a tiny, on board transistor that is in direct contact with a nerve or muscle fiber. When there is a spike in voltage within the fiber, this alters the circuit and the vibration of the crystal, which then changes the echo detected by the ultrasound receiver. The same device will typically generate the same vibrations. This slight change is known as the backscatter which allows researchers to determine the exact voltage.
During their experiment, UC Berkeley’s team powered up passive sensors every 100 microseconds with six 540-nanosecond ultrasound pulses that gave off continual and real time readouts. The first generation motes were coated with surgical grade epoxy but they are currently working on building motes from biocompatible thin films that may potentially last inside the body without any signs of degradation for at least a decade.
So far the experiments have involved peripheral nervous system and muscles, but the neural dust motes could work just as well in the central nervous system and brain in order to control prosthetics according to researchers. Implantable electrodes generally degrade within a year or two and are always connected to wires that must go through holes cut directly in the skull. Wireless sensors, as many as a few dozen to a hundred could be sealed within which would limit infection as well as unwanted movement of the electrodes.
Reference – http://sciencenewsjournal.com/
Edited by – Omkar Joshi .