Diamond-containing electrodes for neurochemical detection

Patent metadata

Field	Value
Publication number	US-2018092575-A1
Application number	US-201715680401-A
Country	US
Kind code	A1
Filing date	Aug 18, 2017
Priority date	Aug 19, 2016
Publication date	Apr 5, 2018
Grant date	—

Abstract

This document provides methods and materials involved in assessing concentrations of analytes in an environment using a diamond-containing carbon electrode. For example, methods and materials for using FSCV or paired pulse voltammetry to discriminate analytes based on their adsorption characteristics to a diamond-containing carbon electrode are described herein.

First claim

1 . An electrode configured to sense an analyte present within an environment, wherein an outer surface of a sensing portion of the electrode is a diamond-containing material that includes a composition of both sp 3 -hybridized carbon and sp 2 -hybridized carbon.

2 . The electrode of claim 1 , wherein the composition of the diamond-containing material includes about 2-percent to about 8-percent sp 2 -hybridized carbon, wherein the composition of the diamond-containing material includes about 92-percent to about 98-percent sp 3 -hybridized carbon.

3 . The electrode of claim 1 , wherein the composition of the diamond-containing material includes about 2-percent to about 30-percent sp 2 -hybridized carbon.

4 . The electrode of claim 1 , wherein the composition of the diamond-containing material includes about 50-percent to about 98-percent sp 3 -hybridized carbon.

5 . The electrode of claim 1 , wherein the diamond-containing material of the outer surface of the sensing portion of the electrode is further doped with one or more material elements to increase electrical conductivity of the diamond-containing material.

6 . The electrode of claim 5 , wherein the one or more material elements includes boron.

7 . The electrode of claim 1 , wherein the diamond-containing material coats at least a portion of a conductive substrate.

8 . The electrode of claim 1 , wherein the conductive substrate comprises conductive material selected from the group consisting of tungsten, silicon, gold, platinum, and rhenium.

9 . The electrode of claim 1 , wherein a second portion of the electrode is coated in parylene, wherein the second portion is different from the sensing portion.

10 . The electrode of claim 1 , wherein the environment comprises brain tissue of a mammal.

11 - 13 . (canceled)

14 . An apparatus for sensing an analyte present within an environment, the apparatus comprising:
an electrical power source; and a probe that is configured (i) to apply, using energy delivered from the electrical power source, an electrical stimulus to tissue of a mammal within the environment and (ii) to detect, within the environment, a response to the electrical stimulus that indicates a level of the analyte present within the environment; wherein the probe includes an electrode for at least one of applying the electrical stimulus or detecting the response to the electrical stimulus, wherein the probe is made at least in part from a diamond-containing carbon material that includes a composition of both sp3-hybridized carbon and sp 2 -hybridized carbon.

15 . The apparatus of claim 14 , wherein the composition of the diamond-containing carbon material includes about 2-percent to about 8-percent sp 2 -hybridized carbon, wherein the composition of the diamond-containing carbon material includes about 92-percent to about 98-percent sp 3 hybridized carbon.

16 . The apparatus of claim 14 , wherein the composition of the diamond-containing carbon material includes about 2-percent to about 30-percent sp 2 -hybridized carbon.

17 . The apparatus of claim 14 , wherein the composition of the diamond-containing carbon material includes about 50-percent to about 98-percent sp 3 -hybridized carbon.

18 . The apparatus of claim 14 , wherein the diamond-containing carbon material is further doped with one or more material elements to increase electrical conductivity of the diamond-containing carbon material.

19 . The apparatus of claim 18 , wherein the one or more material elements includes boron.

20 . The apparatus of claim 14 , wherein the electrode has an elongated geometry and includes a first end having a conically-shaped tip, wherein the conically-shaped tip includes a conductive outer layer made of the diamond-containing carbon material.

21 . The apparatus of claim 14 , wherein the electrode comprises an insulated portion and a conductive portion, wherein the conductive portion includes a conductive outer layer made of the diamond-containing carbon material.

22 . The apparatus of claim 21 , wherein the insulated portion comprises an elongated cylindrical rod.

23 . The apparatus of claim 22 , wherein the elongated cylindrical rod is made of at least one of tungsten, a platinum group metal, a platinum alloy, or a silicon containing material.

24 . The apparatus of claim 14 , wherein:
the probe is configured to apply the electrical stimulus to brain tissue in a region of a brain of the mammal, the probe is configured to detect a response that indicates a level of a neurochemical or ion that is present in the region of the brain, and the apparatus further comprises a processing unit in wireless communication with the probe, wherein the processing unit is configured (i) to receive information from the probe about the response that indicates the level of the neurochemical or the ion that is present in the region of the brain and (ii) to send information to the probe about at least one of a level or timing of electrical stimulus to apply to the brain tissue.

25 . The apparatus of claim 14 , wherein the probe is configured to detect the response that indicates the level of the neurochemical or the ion that is present in the region of the brain using a fast-scan cyclic voltammetry technique.

26 . The apparatus of claim 14 , wherein the probe is configured to detect the response that indicates the level of the neurochemical or the ion that is present in the region of the brain using an amperometry technique.

27 - 34 . (canceled)

35 . A method comprising:
locating a probe that includes the electrode of any of claims 1 - 9 in a region of a brain of a mammal; generating, with the probe, an electrical stimulus and applying the electrical stimulus to brain tissue of the mammal; monitoring a response to the electrical stimulus that occurs in the region of the brain of the mammal, including sensing with the electrode a neurochemical or an ion in the region of the brain of the mammal that results from the electrical stimulus; and outputting information about the level of the neurochemical or the ion in the region of the brain of the mammal that results from the electrical stimulus.

Assignees

• Mayo Found Medical Education & Res

Inventors

• Bennet Kevin E
• Lee Kendall H

Classifications

• A61B5/6868

  Brain · CPC title

• A61N1/0534

  Electrodes for deep brain stimulation · CPC title

• A61N1/36121

  Production of neurotransmitters; Modulation of genes expression · CPC title

• A61B5/14546

  for measuring analytes not otherwise provided for, e.g. ions, cytochromes · CPC title

• A61B5/4064

  Evaluating the brain (for intracranial pressure A61B5/031; for cerebral blood gases A61B5/14553; using EEG A61B5/369) · CPC title