A Sydney researcher has combined industry experience working in sensor technologies and biomedical devices to develop a printable device that acts like a retina – with potential to restore sight to blind people.
Dr Matthew Griffith, from the University of Sydney’s School of Aerospace, Mechanical and Mechatronic Engineering, and the Australian Centre for Microscopy and Microanalysis, has created an electrical device from multi-coloured carbon-based semiconductors. It uses absorbed light to fire the neurons that transmit signals from the eyes to the brain, acting as an artificial retina for those who have lost this capacity.
The device can be printed using the same, low-cost method as newspaper printing, with a high-speed roll-to-roll press.
Griffith, who has translated laboratory innovations to applied product development for multiple national and international partners, hopes the device will help the 2.2 billion people living with vision impairment worldwide.
“Our research aims to provide a biomedical solution to those experiencing blindness from retinitis pigmentosa and age-related macular degeneration (AMD), the second being one of the leading causes of blindness in the world,” Griffith said.
He wants to ultimately apply the technology – a type of neural interface that interacts with an individual’s nervous system to record or stimulate activity – to restore sensory function to those with spinal cord injuries, and to treat people with neurodegenerative diseases.
“Among other functions, neurons are the body’s signal conductors. A missing neuron link, which can be caused by, for example, a spinal cord injury, can cause severe problems. It can also be debilitating if neurons misfire – this can cause blindness and deafness, as well as diseases like Parkinson’s and epilepsy, for which there is no cure,” he said.
“Neural interfaces can bridge this neuronal divide, or, in the case of misfiring, re-program the neurons.”
Leading a research team at the nexus between chemistry, physics, and biomedical engineering, Griffiths said similar technologies are being developed, but his device differs in that it is made of carbon.
“Other devices tend to be rigid and usually made of silicon or metal, which can present problems integrating with the human body that is soft and flexible. Our organic device is designed with this issue in mind,” he said.
It’s intended the device will be printed on to soft and flexible surfaces from water-based inks that contain nerve growth factors and then inserted into a patient’s retina by a surgeon.
Once the relevant neurons reconnect to it, the retina will regain lost functionality when stimulated with light. At this stage, Griffith and his team have conducted experiments using neurons from the spinal cord and eyes of mice.
Early experiments examined the growth of mice neuronal cells onto the semiconductors in a petri dish, after which the electrical activity of the neurons was tested.
“Not only did these cells survive – they grew and maintained neural functionality,” Griffith said.
“The next step is to control where they grow by printing nanopatterns. This is so in future, we can direct them to grow into specific bodily locations, like a spinal cord or retina.”
Griffith has been awarded an NHMRC Ideas grant to continue work on the project together with colleagues from the University of Sydney and neurobiologists from the University of Newcastle.
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