CONTACT LENSES HAVING TWO-ELECTRODE ELECTROCHEMICAL SENSORS

• US 20140190839A1
• Filed: 08/06/2012
• Published: 07/10/2014
• Est. Priority Date: 08/06/2012
• Status: Abandoned Application

• Current Assignee: Verily Life Sciences LLC (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: Liu, Zenghe
• Application Number:
  US13/568,078
• Publication Number:
  US 20140190839A1
• Time in Patent Office: Days
• US Class Current: 205/775
• CPC Class Codes: A61B 5/0004 characterised by the type of physiological signal transmitted
• CPC Class Codes: A61B 5/002 Monitoring the patient using a local or closed circuit, e.g. in a room or building A61B5/0017 takes precedence
• CPC Class Codes: A61B 5/14507 specially adapted for measuring characteristics of body fluids other than blood devices for taking samples of body liquids A61B10/0045
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/1486 using enzyme electrodes, e.g. with immobilised oxidase
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: A61B 5/6821 Eye

Abstract

Apparatus, systems and methods employing contact lenses with two-electrode electrochemical sensors are provided. In some aspects, the contact lens includes: a substrate that forms at least part of a body of the contact lens; and a circuit, disposed on or within the substrate, and including a two-electrode electrochemical sensor. The two-electrode electrochemical sensor can include: a working electrode; and a combination reference-counter electrode. The electrochemical sensor can be an amperometric sensor that senses a biological feature of a wearer of the contact lens. The working electrode can generate a signal indicative of the sensed analyte, and the combination reference-counter electrode can pass the signal generated from the working electrode. The signal can be employed to determine the analyte concentration of a solution in contact with the contact lens.

Claims

1. A contact lens, comprising:

a substrate that forms at least part of a body of the contact lens; and

a circuit, disposed on or within the substrate, and comprising a two-electrode electrochemical sensor, wherein the two-electrode electrochemical sensor comprises;

a working electrode; and

a combination reference-counter electrode.

2. The contact lens of claim 1, wherein the working electrode generates a signal indicative of a sensed analyte.

3. The contact lens of claim 2, wherein the combination reference-counter electrode passes the signal generated from the working electrode.

4. The contact lens of claim 1, wherein the working electrode and the combination reference-counter electrode are comprised of a same material.

5. The contact lens of claim 1, wherein the working electrode is comprised of platinum and the combination reference-counter electrode is comprised of a noble metal.

6. The contact lens of claim 1, wherein the combination reference-counter electrode is comprised of at least one of carbon or silver/silver chloride.

7. The contact lens of claim 1, wherein the two-electrode electrochemical sensor comprises a hydrogen peroxide sensor with two platinum electrodes.

8. The contact lens of claim 1, wherein the two-electrode electrochemical sensor is an amperometric sensor.

9. The contact lens of claim 8, wherein the amperometric sensor is a biosensor that senses a level of at least one of glucose, protein, triglycerides, urea or lactate in a body of a wearer of the contact lens.

10. The contact lens of claim 8, wherein the amperometric sensor comprises a working electrode having glucose oxidase deposited on the working electrode.

11. The contact lens of claim 1, wherein the working electrode is smaller than the combination reference-counter electrode.

12. The contact lens of claim 11, wherein a ratio of an area of the combination reference-counter electrode and an area of the working electrode is between 2 and 10000.

13. A contact lens, comprising:

a substrate that forms at least part of a body of the contact lens; and

a circuit, disposed on or within the substrate, and comprising a two-electrode electrochemical sensor.

14. The contact lens of claim 13, wherein the two-electrode electrochemical sensor comprises a hydrogen peroxide sensor with two platinum electrodes.

15. The contact lens of claim 13, wherein the two-electrode electrochemical sensor is an amperometric sensor.

16. The contact lens of claim 15, wherein the amperometric sensor is a biosensor that senses at least one of glucose, protein, triglycerides, urea or lactate.

17. The contact lens of claim 15, wherein the amperometric sensor comprises a working electrode having glucose oxidase deposited on the working electrode.

18. The contact lens of claim 13, wherein components of the two-electrode electrochemical sensor are comprised of a same material.

19. A method, comprising:

determining a diffusion controlled region on a voltammogram; and

determining a potential to be applied to a two-electrode electrochemical sensor of a contact lens, wherein the potential is substantially equivalent to a potential to be applied to a three-electrode electrochemical sensor of a contact lens, and the determining the potential being based on the diffusion controlled region.

20. The method of claim 19, wherein the determining the diffusion controlled region comprises performing one or more voltammetry experiments to determine the diffusion controlled region.