A nanomaterial has been developed that stimulates and repairs torn nerves
Magneto-optical material was used to precisely remotely stimulate neurons and repair a gap in a damaged nerve in a rat model.Neuroengineers from Rice University have developed tiny particles with magneto-optical properties to stimulate nerve tissue. The effectiveness of the material was confirmed in experiments on rats. The technology will allow the development of injectable particles to replace large neuroimplants.
The device is a magnetoelectric: it generates electricity under the influence of a magnetic field. The metamaterial consists of two layers of metallic glass alloy Metglas, between which is placed a piezoelectric layer of lead-zirconium titanate.
Piezoelectric materials generate electricity by mechanical forces. Metglas is a magnetostrictive material, meaning it changes shape under the influence of a magnetic field. In the finished device, the change in shape of the outer layers under the action of magnetic pulses causes the piezoelectric material in the center to generate an electrical signal.
Magnetoelectrics have already been tested in neuroscience. For example, a 2021 study showed how magnetoelectric devices transmit signals wirelessly, replacing the signaling pathway of damaged neurons. But magnetoelectric signals tend to be too fast for human nerves to pick up.
To solve this problem, the researchers enlarged the magnetoelectric film by adding platinum oxide, hafnium oxide and zinc oxide. Despite the multilayer structure, the film was only about 200 nm thick. The modification allowed the optimal frequency to be obtained for precisely calculated neural stimulation.
The finished material was tested on rats and found to stimulate peripheral nerve function in rodents under anesthesia, as well as restoring the function of the transected sciatic nerve. The technology will be suitable for developments in neuroprosthetics and sensor control in microelectronics.