(she/her/hers)
University of Minnesota, Twin Cities
MEMs, neuromodulation, micromagnetics, spintronics, nanotechnology, healthcare
Renata Saha is a 5th year PhD Candidate in the Department of Electrical & Computer Engineering at the University of Minnesota, Twin Cities. She received her Bachelor’s in Technology (B.Tech) from National Institute of Technology, Durgapur, India. In the summer of 2017, she was an undergraduate research intern at Conseil européen pour la recherche nucléaire (CERN), Geneva, Switzerland. She is the recipient of 3-year College of Science & Engineering Fellowship, Women in Technology Scholarship 2021-2022 from Cadence Design Systems, elected iREDEFINE Fellow 2022 by Electrical & Computer Engineering Department Heads Association (ECEDHA) and recipient of Minnesota’s Discovery, Research and InnoVation Economy (MnDRIVE) Fellowship 2022-2023. She has published over 27 publications, 2 US patents and 1 book chapter. She is the recipient of 2 Best Poster Awards and 2 Travel Awards. Her research interest includes development of microelectromechanical systems (MEMs)-based micromagnetic devices for their application in clinical settings.
Exploring Implantable Micromagnetic Neurostimulation as an Alternative to Electrode Stimulation
Micromagnetic stimulation (μMS), although still in its infancy, is a neuromodulation technique which are deep brain stimulation (DBS)-like implants but work on the physics of transcranial magnetic stimulation (TMS). The devices are implantable microcoils (μcoils) which when driven by an alternating current, generates a time varying magnetic field which as per Faraday’s Laws of Electromagnetic Induction induces an electric field. This induced electric field activates the neurons. Since this induced electric field is not in direct galvanic contact with the tissues, these µcoils are safer compared to electrical implants in terms of biofouling nuances. In addition, numerical studies have shown significantly less tissue heating from these µcoils in an MRI environment, thereby yielding MRI compatible brain stimulation implants. Through interdisciplinary collaboration among 5 departments at UMN and Mayo Clinic, Rochester, MN we have developed two µMS implants, each targeted for various neurodegenerative applications: First, Magnetic Pen(MagPen), the single µcoil prototype; second, Magnetic Patch(MagPatch), the µcoil array prototype. In an in vitro study, the MagPen has been reported to activate the hippocampal CA3-CA1 synaptic pathway. In an in vivo study, the MagPen has been reported to activate the rat sciatic nerve resulting in a dosage-response curve for µMS. The MagPen has also been able to activate the medial forebrain bundle (MFB) in vivo, in mice, where using fast scan cyclic voltammetry (FSCV) principle we have been able to control dopamine changes in the striatum. In an ongoing experiment, we are trying to investigate MagPen’s efficacy on the rat vagus nerve, control hypertensive activity involving blood pressure, heart rate and respiration rate recorded from the femoral artery.
The MagPen prototype had its own caveats in terms of mm-size, lack of multidimensional spatial control and activation at the cellular-level. To bridge this research gap, we designed the MagPatch Array for further μMS study. To demonstrate single cell activation from MagPatch Array, we are culturing SH-SY5Y human neuroblastoma cell line (ATCC, CRL-2266) directly on the μcoil arrays. The final biocompatible packaging has been made to support MagPatch Array sterilization in an autoclave before the cell culture. To test the bulk biocompatibility for successful growth of healthy SH-SY5Y cell network, we have successfully adhered the cells to Parylene-C. Furthermore, we have shown Ca-concentration changes on application of external chemical stimuli to the adhered cells; meaning the SH-SY5Y cells growing on Parylene-C are alive. Detecting the Ca concentration changes from magnetic stimulation from μcoil array in MagPatch is ongoing.