# US 11,439,810 B2 · Tunable neural electrode > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,439,810 B2 - Document ID: US11439810B2 - Status: Granted - Kind: B2 - Application number: 16/039,071 - Filed: 2018-07-18 - Published: 2019-01-24 - Granted: 2022-09-13 - Earliest claimed: 2017-07-18 - Assignees: Regents of the University of Minnesota - Applicants: Regents of the University of Minnesota - Inventors: Corey Edward Cruttenden; Rajesh Rajamani; Wei Chen; Xiao-Hong Zhu; Mahdi Ahmadi - Web page: https://patentgrep.com/patent/US11439810B2 ## CPC - A61N 1/0534: {Electrodes for deep brain stimulation} - A61B 5/24: Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof - A61B 5/7207: {of noise induced by motion artifacts} - A61N 1/0551: {Spinal or peripheral nerve electrodes} - A61N 1/086: {Magnetic resonance imaging [MRI] compatible leads} - A61B 5/6868: {Brain} - A61B 5/6877: {Nerve} - A61B 2562/125: characterised by the manufacture of electrodes - A61N 1/36003: {of motor muscles, e.g. for walking assistance} - A61N 1/36053: {adapted for vagal stimulation (A61N1/36114 takes precedence)} - A61N 1/36062: {Spinal stimulation} - A61N 1/36067: {Movement disorders, e.g. tremor or Parkinson disease (stimulating motor muscle A61N1/36003)} - A61N 1/36103: {Neuro-rehabilitation; Repair or reorganisation of neural tissue, e.g. after stroke} - A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B) - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract A device includes a substrate, an electrode, an electrical pad, and a signal line. The signal line is coupled to the substrate and covered by an insulation layer. The signal line is coupled to the electrical pad and the electrode. At least one of the electrode and the signal line includes a diamagnetic material and paramagnetic material, wherein a ratio of the diamagnetic material and the paramagnetic material is selected based on the susceptibility properties of a physiological tissue. The term paramagnetic herein refers to magnetic susceptibility greater than that of the surrounding tissue and diamagnetic refers to magnetic susceptibility lower than that of the tissue. ## Claims ### Claim 1 A device comprising: a substrate having a surface; a signal line coupled to the substrate and covered by an insulation layer; an electrical pad coupled to the signal line; and an electrode coupled to the signal line, the electrode comprising a network of randomly oriented conductive nanorods of diamagnetic material and paramagnetic material, wherein diamagnetic and paramagnetic are relative to a physiological tissue, wherein a ratio of the diamagnetic material and the paramagnetic material is selected based on a physiological susceptibility property of the tissue. ### Claim 2 (depends on 1) The device of claim 1, wherein the physiological tissue is a neural or spinal tissue, and the electrode is part of an array of neural electrodes. ### Claim 3 (depends on 1) The device of claim 1, wherein the physiological tissue includes a muscular tissue. ### Claim 4 (depends on 1) The device of claim 1, where the electrode is a recording electrode or a stimulating electrode. ### Claim 5 (depends on 1) The device of claim 1, wherein the signal line includes a network of randomly oriented conductive materials configured to reduce eddy current generation in a MRI system. ### Claim 6 A fabrication method comprising: providing a substrate having a surface; forming a signal line coupled to the substrate; forming an electrical pad coupled to the signal line; forming an electrode, such that the electrode is coupled to the signal line, the electrode comprises a network of randomly oriented conductive nanorods of diamagnetic material and paramagnetic in a ratio based on a physiological susceptibility property of a physiological tissue, wherein diamagnetic and paramagnetic are relative to the physiological tissue; and applying an insulation layer to the signal line. ### Claim 7 (depends on 6) The method of claim 6, wherein the ratio is a volumetric ratio. ### Claim 8 (depends on 6) The method of claim 6, further comprising: selecting the ratio to substantially match the magnetic susceptibility with that of the physiological tissue. ### Claim 9 (depends on 6) The method of claim 6, wherein forming the electrode includes depositing layers of the diamagnetic and paramagnetic materials. ### Claim 10 (depends on 6) The method of claim 6, wherein forming the electrode includes forming layers of diamagnetic material and paramagnetic material to substantially match the physiological susceptibility property of the physiological tissue. ### Claim 11 (depends on 6) The method of claim 6, wherein forming the electrode includes diffusion of the paramagnetic and diamagnetic materials to substantially match the physiological susceptibility property of the physiological tissue. ### Claim 12 (depends on 6) The method of claim 6, wherein forming the electrode includes evaporating and heating. ### Claim 13 (depends on 6) The method of claim 6, wherein forming the electrode includes co-depositing the diamagnetic material and the paramagnetic material. ### Claim 14 (depends on 6) The method of claim 6, wherein forming the signal line includes forming the signal line to include a network of randomly oriented conductive materials selected from the group consisting of: conductive nanorods, nanomaterials, and micro-structured conductive materials. ### Claim 15 (depends on 6) The method of claim 6, further comprising: forming a variety of MRI-compatible and biocompatible electrodes with particular susceptibility that substantially matches the tissue susceptibility for neural recording and brain stimulation with minimal MRI susceptibility artifacts or reduced eddy current and tissue heating. ### Claim 16 A neural electrode array device comprising: a substrate; a signal line coupled to the substrate; an insulation layer covering the signal line; an electrical pad coupled to the signal line; and an electrode coupled to the signal line, wherein the electrode includes a network of randomly oriented conductive nanorods of diamagnetic material and paramagnetic material configured to reduce eddy current generation in a MRI system, wherein diamagnetic and paramagnetic are relative to a neural tissue. ### Claim 17 (depends on 16) The device of claim 16, wherein the signal line is fabricated of a material having a susceptibility property corresponding to neural tissue. ### Claim 18 (depends on 16) The device of claim 16, wherein the electrode includes a layer of carbon nanotubes at an exposed surface. ### Claim 19 (depends on 16) The device of claim 16, wherein the electrode includes a layer of electrically conductive polymer at an exposed surface. ### Claim 20 (depends on 16) The device of claim 16, wherein the electrode includes a layer of biocompatible conductive material at an exposed surface. ### Claim 21 (depends on 16) The device of claim 16, wherein the substrate has a magnetic susceptibility that substantially matches that of the neural tissue.