A model for the smallest working sensor has been developed by University of California, Berkeley researchers. This new sensor is no larger than a grain of rice and the next wave is likely to be no larger that a speck of dust. The sensors have a range of potential medical benefits, from collecting important information about the status of organs to helping those fitted with prosthetic limbs to control movements seamlessly through nerve impulses.
At the heart of the new generation of sensors is a piezoelectric crystal. Piezoelectricity refers to the process whereby an electric charge accumulates in a solid material (like a crystal), in response to applied mechanical stress. Detection of pressure variations in the form of sound is the most common sensor type, and ultrasound is key to the operation of the new sensors.
The device capable of converting ultrasound vibrations into usable energy. This process also allows the device to transmit data collected from nerve cells to the brain, and it is this functionality that holds the key to an amputee fitted with a bionic limb to control the movement of the artificial appendage.
At present the development of the sensor remains a ‘proof-of-concept’ study. To get the sensor to work within a human for the application of bionics the sensor needs to made much smaller, which is where the ‘dust size’ comes (the researchers behind the study prefer the term “neural dust”), as lead researcher Dr. Ryan Neely explained to Engadget:
“The original goal of the neural dust project was to imagine the next generation of brain-machine interfaces, and to make it a viable clinical technology. If a paraplegic wants to control a computer or a robotic arm, you would just implant this electrode in the brain and it would last essentially a lifetime.”
The way the biosensor would work is detailed in the following video:
The next steps involve shrinking the size and running some studies using an animal model. If this goes well, a human trial may not be that far away.
The development has been outlined in the journal Neuron, which the research paper headed “Wireless Recording in the Peripheral Nervous System with Ultrasonic Neural Dust.”
