Researchers from the University of Minnesota and Mayo Clinic to develop magnetic nanodevice arrays to treat neurological diseases

A project jointly undertaken by scientists from ECE, the departments of Neurosurgery, and Biomedical Engineering, and the Mayo Clinic has received close to $1 million in a grant from the Minnesota Partnership for Biotechnology and Medical Genomics. The project is titled, “Magnetic Nanodevice Arrays for the Treatment of Neurological Diseases.” The funding will enable the team to develop an implantable magnetic nanodevice array with the ability to generate highly localized magnetic fields for neuromodulation. 

The project will be led by Distinguished McKnight University Professor and Robert F. Hartmann Chair in Electrical Engineering, Jian-Ping Wang (ECE), and Prof. Kendall H. Lee of the Mayo Clinic. Other investigators on the team are Prof. Tay Netoff (Dept. of Biomedical Engineering), and Prof. Walter C. Low (Dept. of Neurosurgery). The grant is spread over 2 years, effective February 2020.

Prof. Netoff, co-investigator on the project, and Director of the Center for Neuroengineering shares his enthusiasm about the possibilities: “I am excited about the prospects of magnetic stimulation of neural tissue with high resolution. Until now, neural populations could only be stimulated at small scales using electrical stimulation. Different neuronal populations may be excited with magnetic stimulation and this technology may provide the opportunity for new therapies.”

Electrical and magnetic fields are used for therapeutic purposes, such as restoring hearing, treatment of Parkinson’s disease, epilepsy, stroke, and others. Transcranial Magnetic Stimulation (TMS) is an example of the use of magnetic fields, and Deep Brain Stimulation (DBS) uses electric fields. Although the two types of stimulation have similar effects on neurons, their differences impact their effectiveness. In DBS, the electrical stimulation depends on electrochemical interaction with the surrounding tissue for the passage of an electric current, which can be adversely affected by factors such as degradation of the electrode or corruption of the electrode by biological debris. Currently, this issue is resolved by increasing the electric field through increased voltage or current pulses. The resulting side effects can be mitigated by re-programming the device, but alleviation is typically only a partial remedy. Other challenges that electric stimulation pose include limitations on current density, so very small electrodes cannot deliver high currents. On the other hand, TMS, although non-invasive,  is limited to stimulation of cortical surfaces and cannot stimulate structures deeply located in the brain which are targets of neurological disorders such as Parkinson’s disease and essential tremor.

Commenting on the groundbreaking nature of the research, Dr. Kai Wu (postdoctoral research associate with ECE and member of the research team) says: “Nanometer-scale devices exploiting spintronics can be a key technology in the fields of neuroscience and neural engineering. Magnetic spintronic nanodevices offer a plethora of novel mechanisms which can be harnessed into new device paradigms with the potential to drive progress in the sensing and modulation of neuron activities.”

To counter these challenges, the award winning team has developed a novel nanodevice technology that can allow localized magnetic stimulation through magnetic nanodevices. These magnetic stimulators can be completely enclosed extending their life expectancy. In the current project, the team will go on to develop an implantable magnetic nanodevice array that can generate a highly localized magnetic field for neuromodulation. 

Organized into 2 stages, stage 1 of the project will involve the development of a prototype of functional magnetic nanodevice arrays, and in vitro testing of the prototype. In stage 2, the magnetic nanodevice arrays will be transferred onto medical grade, implantable, flexible substrates, and then tested in vivo.

The project aligns with, and will contribute to the NIH Brain Initiative that seeks to develop new technologies for the large-scale recording and neuromodulation of brain activities for the treatment of neurological diseases such as Parkinson’s disease, essential tremor, Tourette’s syndrome, depression, and others.

Co-principal investigator and Director of Mayo Clinic Neural Engineering Laboratories Dr Kendall H. Lee points to the future of therapeutic options: “This project represents a new trend of future implantable brain stimulation technology using spintronic nanodevice arrays. It could allow large area stimulation of neuronal activities with sub-cellular scale resolution.”

The team expects that the proposed development and rigorous pre-clinical testing of a flexible magnetic nanostimulator platform for brain neuromodulation will provide a substantially novel and more effective therapeutic device to treat neuropsychiatric diseases over present conventional devices.

*The post image is courtesy Tumisu from Pixabay