ENHANCED SENSOR FOR A CONTINUOUS BIOLOGICAL MONITOR

• US 20190310218A1
• Filed: 04/05/2019
• Published: 10/10/2019
• Est. Priority Date: 04/06/2018
• Status: Active Grant

• Current Assignee: Zense-Life, Inc.
• Original Assignee: Zense-Life, Inc.
• Inventors: Boock, Robert James, Zhang, Huashi
• Granted Patent: US 11,576,595 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 2562/125 characterised by the manufacture of electrodes
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14865 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors
• CPC Class Codes: C12N 9/0006 acting on CH-OH groups as donors (1.1)
• CPC Class Codes: C12Q 1/002 Electrode membranes
• CPC Class Codes: C12Q 1/006 for glucose
• CPC Class Codes: C12Y 101/01027 L-Lactate dehydrogenase (1.1.1.27)
• CPC Class Codes: C12Y 101/0103 3-Hydroxybutyrate dehydrogenase (1.1.1.30)
• CPC Class Codes: C12Y 101/03004 Glucose oxidase (1.1.3.4)
• CPC Class Codes: C25D 7/0607 Wires
• CPC Class Codes: C25D 9/02 with organic materials
• CPC Class Codes: G01N 27/3271 Amperometric enzyme electrodes for analytes in body fluids, e.g. glucose in blood amperometry per se G01N27/49; aspects concerning the enzyme reagent C12Q1/001
• CPC Class Codes: G01N 27/3275 Sensing specific biomolecules, e.g. nucleic acid strands, based on an electrode surface reaction
• CPC Class Codes: H01M 2004/024 Insertable electrodes
• CPC Class Codes: H01M 4/02 Electrodes composed of, or comprising, active material
• CPC Class Codes: H01M 4/0402 Methods of deposition of the material
• CPC Class Codes: H01M 4/0419 involving spraying
• CPC Class Codes: H01M 4/045 Electrochemical coating; Electrochemical impregnation
• CPC Class Codes: H01M 4/1395 of electrodes based on metals, Si or alloys
• CPC Class Codes: H01M 4/1399 of electrodes based on electro-active polymers
• CPC Class Codes: H01M 4/96 : Carbon-based electrodes
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02E 60/50 : Fuel cells

Abstract

Briefly, a sensor for a continuous biological monitor is provided for measuring the level of a target analyte for a patient. The sensor has a working wire and a reference wire, where the working wire has an analyte limiting layer that passes more than 1 in 1000 analyte molecules from the patient to the an enzyme layer . The enzyme layer has an enzyme entrapped in a polyurethane cross-linked with acrylic polyol. As free electrons are generated, a conductor transfers the electrons to the biological monitor. In some cases, the sensor may be constructed without the use of any expensive platinum.

Claims

1. A sensor for a continuous glucose monitor that is subcutaneously inserted into a patient, comprising:

a working electrode, comprising;

a glucose limiting layer having a hydrophobic bonding material and a hydrophobic bonding material that are physically cross-linked;

an enzyme layer comprising polyurethane with a self cross-linking acrylic polyol for entrapping GOx, the GOx reacting with the patient'"'"'s glucose to generate peroxide and thus free electrons in proportion to the level of glucose in the patient'"'"'s blood; and

a conductor for passing the free electrons to the glucose monitor for measurement; and

a substrate; and

a reference electrode.

2. The working electrode according to claim 1, wherein the enzyme layer also functions as the conductor, and the enzyme layer further comprises carbon materials.

3. The working electrode according to claim 2, wherein the carbon materials comprise carbon, graphite, graphene, or pyrolytic graphite.

4. The working electrode according to claim 1, wherein the conductor comprises carbon materials, and the substrate is plastic.

5. The working electrode according to claim 1, wherein the conductor is platinum, and the substrate is a metal.

6. The working electrode according to claim 1, wherein the conductor and substrate are platinum.

7. The working electrode according to claim 1, further including an interference layer positioned between the enzyme layer and the glucose limiting layer, the interference layer being permselectable to block the passage of molecules over a defined molecular weight.

8. The working electrode according to claim 1, further including an interference layer positioned between the enzyme layer and the conductor, the interference layer being permselectable to block the passage of molecules over a defined molecular weight.

9. The working electrode according to claim 1, wherein physical cross linking in the glucose limiting layer is in the form of hydrogen bonding.

10. The sensor according to claim 1, wherein the working electrode has a first flat surface and the reference electrode has a second flat surface, and the first and second flat surfaces are attached.

11. The sensor according to claim 10, wherein the working electrode and the reference electrode are each half-wires with semi-circular cross-sections.

12. The sensor according to claim 10, wherein an electrochemical element is on the first flat surface.

13. The sensor according to claim 12, wherein the electrochemical element is a carbon material.

14. The working electrode according to claim 1, further including a counter electrode, and wherein the working electrode has a first flat surface, the reference electrode has a second flat surface and the counter electrode has a third flat surface, and each flat surface is attached to a common support core.

15. The working wire according to claim 14, wherein the support core is triangular is shape, and each respective flat surface is attached to one of the faces of the triangle.

16. The sensor according to claim 1, wherein the working electrode is in the form of an elongated wire.

17. A sensor for a continuous biological monitor that is subcutaneously inserted into a patient, comprising:

a working electrode, comprising;

a target-analyte limiting layer having a hydrophobic bonding material and a hydrophobic bonding material that are physically cross-linked;

an enzyme layer comprising polyurethane with a self cross-linking acrylic polyol for entrapping GOx, the GOx reacting with the patient'"'"'s glucose to generate peroxide and thus free electrons in proportion to the level of glucose in the patient'"'"'s blood; and

a conductor for passing the free electrons to the biological sensor for measurement; and

a substrate; and

a reference electrode.

18. The method according to claim 17, wherein the enzyme is GOx, lactate dehydrogenase or hydroxybutyrate dehydrogenase.

19. The working electrode according to claim 17, wherein the enzyme layer also functions as the conductor, and the enzyme layer further comprises carbon materials.

20. The working electrode according to claim 19, wherein the carbon materials comprise carbon, graphite, graphene, or pyrolytic graphite.

21. The working electrode according to claim 17, wherein the conductor comprises carbon materials, and the substrate is plastic.

22. The working electrode according to claim 17, wherein the conductor is platinum, and the substrate is a metal.

23. The working electrode according to claim 17, wherein the conductor and substrate are platinum.

24. The working electrode according to claim 17, further including an interference layer positioned between the enzyme layer and the glucose limiting layer, the interference layer being permselectable to block the passage of molecules over a defined molecular weight.

25. The working electrode according to claim 17, further including an interference layer positioned between the enzyme layer and the conductor, the interference layer being permselectable to block the passage of molecules over a defined molecular weight.

26. The working electrode according to claim 17, wherein the physical cross linking in the analyte limiting layer is in the form of hydrogen bonding.