CONTROLLED ELECTROCHEMICAL ACTIVATION OF CARBON-BASED ELECTRODES

• US 20150168331A1
• Filed: 02/27/2015
• Published: 06/18/2015
• Est. Priority Date: 11/23/2009
• Status: Active Grant

• Current Assignee: Proxim Diagnostics, Proxim Diagnostics Corporation
• Original Assignee: Proxim Diagnostics
• Inventors: Briman, Mikhail
• Granted Patent: US 10,041,900 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01N 27/26 by investigating electrochemical variables; by using electrolysis or electrophoresis
• CPC Class Codes: G01N 27/30 Electrodes, e.g. test electrodes; Half-cells G01N27/414 takes precedence
• CPC Class Codes: G01N 27/327 Biochemical electrodes , e.g. electrical or mechanical details for in vitro measurements
• CPC Class Codes: G01N 27/3276 being a hybridisation with immobilised receptors using a FET type sensor G01N27/4145; concerning the hybridisation C12Q1/68
• CPC Class Codes: G01N 27/38 Cleaning of electrodes

Abstract

Certain embodiments of the present application describe a process to perform activation of carbon based electrodes in a controlled manner, where the degree of activation is monitored and calculated simultaneously with the ongoing activation process. Such an approach is intended to improve the reproducibility of electrodes that may include, but are not limited to, the following parameters: electrochemical capacitance, electrochemical transfer coefficient, amperiometric response to enzymatic reactions.

Claims

1. An electrochemical sensor, comprising:

a reference electrode;

a first carbon-based sensor electrode having a first electrochemical capacitance with respect to the reference electrode;

a second carbon-based sensor electrode having a second electrochemical capacitance with respect to the reference electrode; and

an aqueous solution, wherein the reference electrode, the first carbon-based sensor electrode and the second carbon-based sensor electrode are exposed to the aqueous solution, and

wherein the first electrochemical capacitance and the second electrochemical capacitance are substantially the same.

2. The electrochemical sensor of claim 1, further comprising a means for measuring the first electrochemical capacitance and the second electrochemical capacitance.

3. The electrochemical sensor of claim 2, further comprising a means for controlling a voltage applied to the reference electrode.

4. The electrochemical sensor of claim 3, further comprising a means for measuring a first current in the first carbon-based sensor electrode, and a second current in the second carbon-based sensor electrode.

5. The electrochemical sensor of claim 4, wherein the first electrochemical capacitance and the second electrochemical capacitance have a value between 4 uF/cm̂

2 and 10 uF/cm̂

2.

6. The electrochemical sensor of claim 5, wherein the first electrochemical capacitance and the second electrochemical capacitance have a CV% between 0.4% and 1%.

7. The electrochemical sensor of claim 1, wherein the first electrochemical capacitance and the second electrochemical capacitance have a value between 4 uF/cm̂

2 and 10 uF/cm̂

2, and

wherein the first electrochemical capacitance and the second electrochemical capacitance have a CV% between 0.4% and 1%.

8. The electrochemical sensor of claim 7, further comprising a means for cyclically applying a first electric potential to the first carbon-based sensor electrode and a second electric potential to the second carbon-based sensor electrode versus the reference electrode.

9. The electrochemical sensor of claim 1, further comprising a means for cyclically applying a first electric potential to the first carbon-based sensor electrode and a second electric potential to the second carbon-based sensor electrode versus the reference electrode.

10. The electrochemical sensor of claim 9, wherein the first electrochemical capacitance and the second electrochemical capacitance have a CV% between 0.4% and 1%.

11. An electrochemical sensor, comprising:

a first carbon-based sensor electrode having a first number of attached functional groups;

a second carbon-based sensor electrode having a second number of attached functional groups; and

an aqueous solution, wherein the first carbon-based sensor electrode and the second carbon-based sensor electrode are exposed to the aqueous solution, and

wherein a first electrochemical capacitance between the first carbon-based sensor electrode and a reference electrode is substantially equal to a second electrochemical capacitance between the second carbon-based sensor electrode and the reference electrode.

12. The electrochemical sensor of claim 11, wherein the first number of attached functional groups is greater than the second number of attached functional groups.

13. The electrochemical sensor of claim 12, wherein the first electrochemical capacitance and the second electrochemical capacitance have a value between 4 uF/cm̂

2 and 10 uF/cm̂

2.

14. The electrochemical sensor of claim 13, wherein the first electrochemical capacitance and the second electrochemical capacitance have a CV% between 0.4% and 1%.

15. The electrochemical sensor of claim 14, further comprising a means for controlled introduction of functional groups to surfaces of the first carbon-based sensor electrode and the second carbon-based sensor electrode through faradaic type reactions.

16. An electrochemical sensor, comprising:

a first carbon-based sensor electrode;

a second carbon-based sensor electrode; and

an aqueous solution, wherein the reference electrode, the first carbon-based sensor electrode and the second carbon-based sensor electrode are exposed to the aqueous solution, and

wherein the electrochemical sensor has signal slope that has increased between 30% and 75% compared to an un-activated electrochemical sensor.

17. The electrochemical sensor of claim 16, wherein a first electrochemical capacitance between the first carbon-based sensor electrode and a reference electrode is substantially equal to a second electrochemical capacitance between the second carbon-based sensor electrode and the reference electrode.

18. The electrochemical sensor of claim 17, wherein the first electrochemical capacitance and the second electrochemical capacitance have a value between 4 uF/cm̂

2 and 10 uF/cm̂

2, and

wherein the first electrochemical capacitance and the second electrochemical capacitance have a CV% between 0.4% and 1%.

19. The electrochemical sensor of claim 18, further comprising a means for controlled introduction of functional groups to surfaces of the first carbon-based sensor electrode and the second carbon-based sensor electrode through faradaic type reactions.

20. The electrochemical sensor of claim 16, further comprising a means for cyclically applying a first electric potential to the first carbon-based sensor electrode and a second electric potential to the second carbon-based sensor electrode versus a reference electrode.