Optically controllable microelectrode array for stimulating cells within a tissue

• US 6,347,250 B1
• Filed: 04/23/1999
• Issued: 02/12/2002
• Est. Priority Date: 10/23/1996
• Status: Expired due to Term

• Current Assignee: Retina Implant AG
• Original Assignee: NMI Natural and Medical Sciences Institute at the University TÜBINGEN
• Inventors: Stelzle, Martin, Weiss, Stefan, Graf, Michael, Nisch, Wilfried, Stett, Alfred, Zrenner, Eberhart, Graf, Heinz Gerhard, Schubert, Markus B., Hierzenberger, Anke, Günther, Elke, Wanka, Harald N.
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US09/298,816
• Time in Patent Office: 1,026 Days
• Field of Search: 607/53, 607/54, 607/116
• US Class Current: 607/54
• CPC Class Codes: A61F 9/08 Devices or methods enabling eye-patients to replace direct visual perception by another kind of perception
• CPC Class Codes: A61N 1/05 for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence
• CPC Class Codes: A61N 1/326 for promoting growth of cells, e.g. bone cells
• CPC Class Codes: A61N 1/36046 of the eye

Abstract

An optically controllable microelectrode array for stimulating cells within a tissue is disclosed. The array comprises a substrate having a surface. The substrate is adapted to be placed on the tissue with the surface adjoining the cells. The substrate further comprises a plurality of electrodes on the surface in contact with the cells for stimulating the cells. The electrodes are dimensioned such that a first surface area on the electrodes in contact with the cells is essentially smaller than a second surface area on the cells in which the cells may be contacted by the electrodes. An electrical stimulus is exerted from the electrodes to the cells under the control of light impinging on the tissue.

Claims

1. An optically controllable microelectrode array for stimulating cells within a tissue, the array comprising

a substrate including at least one light-sensitive layer having a surface for facing a tissue to be stimulated, illuminated portions of said light-sensitive layer being adapted to switch to a stimulating potential when irradiated with light;

and

a plurality of electrodes arranged on said surface and adapted for contact with cells forming said tissue;

wherein each said electrode is operative to cause said stimulating potential to electrically stimulate one or more cells in contact therewith when the electrode and the underlying substrate are irradiated with light.

2. The array of claim 1, wherein said electrodes are arranged on said surface and are electrically isolated from each other.

3. The array of claim 2, wherein said electrodes are formed on said substrate by way of lithography.

4. The array of claim 2, wherein said electrodes are formed by local crystallization within said substrate.

5. The array of claim 1, wherein said electrodes are a part of a switch, said switch being adapted to feed a stimulus to said cell.

6. The array of claim 5, wherein said switch is configured by a plurality of substrate layers and said electrodes.

7. The array of claim 1, wherein said substrate is configured as a retina implant.

8. The array of claim 7, wherein said retina implant is a subretinal implant.

9. The array of claim 7, wherein said retina implant is a subretinal implant being essentially permeable for visible light.

10. An optically controllable microelectrode array for stimulating cells within a tissue, the array comprising

a substrate including at least one light-sensitive layer having a flat surface, said light-sensitive layer being adapted to switch at selected parts thereof to a potential for exerting an electrical stimulus when irradiated at said selected parts;

and

a plurality of at least 16 electrodes arranged on said flat surface;

wherein selected ones of said electrodes in contact with said selected parts of said light-sensitive layer, when irradiated, exert electrical stimuli to cells exposed to said selected ones of said electrodes.

11. The array of claim 10, wherein said plurality of said electrodes on said flat surface comprises at least 256 electrodes exposed toward said tissue.

12. The array of claim 10, wherein said electrodes arranged on said flat surface are electrically isolated from each other.

13. The array of claim 11, wherein said electrodes arranged on said flat surface are electrically isolated from each other.

16. The array of claim 10, wherein said substrate further comprises a semiconductor layer, said semiconductor layer and said microelectrodes forming light-sensitive switches for exerting stimuli to one of said cells in contact with said microelectrode, when irradiated with light impinging an said tissue.

14. An assembly including a tissue formed by a plurality of biological cells and an optically controllable microelectrode array having a surface in contact with said tissue for stimulating said cells within said tissue, each said cell having a surface area exposed toward said surface, said array comprising:

a substrate including at least one light-sensitive layer having a flat surface facing said tissue, said light-sensitive layer being adapted to switch at selected parts thereof to a potential exerting an electrical stimulus when irradiated at said selected parts; and

a plurality of electrodes arranged on said flat surface exposed toward said tissue, each said electrode having a first surface area exposed toward said tissue and dimensioned such that said first surface is substantially smaller than the average surface area of said cells exposed toward said electrodes;

wherein selected ones of said electrodes in contact with said selected parts of said light-sensitive layer, when irradiated, exert electrical stimuli to cells exposed toward said selected ones of said electrodes.

15. The array of claim 14, wherein said electrodes arranged on said flat surface are electrically isolated from each other.

17. The array of claim 15, wherein said plurality of said electrodes on said flat surface comprises at least 16 electrodes exposed toward said tissue.

18. The array of claim 15, wherein said plurality of said electrodes on said flat surface comprises at least 256 electrodes exposed toward said tissue.

19. The array of claim 14, wherein the ratio between said average surface area and said first surface area is between 5 and 10.