Apparatus and Method for Measuring Nitric Oxide in Exhaled Breath

• US 20070240987A1
• Filed: 04/13/2007
• Published: 10/18/2007
• Est. Priority Date: 04/14/2006
• Status: Abandoned Application

• Current Assignee: EmiSense Technologies, LLC (Trelleborg AB)
• Original Assignee: EmiSense Technologies, LLC (Trelleborg AB)
• Inventors: Nair, Balakrishnan G., Henderson, Brett Tamatea, Nachias, Jesse Alan
• Application Number:
  US11/735,154
• Publication Number:
  US 20070240987A1
• Time in Patent Office: Days
• US Class Current: 204/426
• CPC Class Codes: G01N 33/0037 for NOx
• CPC Class Codes: G01N 33/497 of gaseous biological material, e.g. breath
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters

Abstract

A sensing apparatus to measure nitric oxide (NO) in exhaled breath is disclosed. An embodiment of the sensing apparatus includes an inlet, a pretreatment element, and a sensing electrode. The inlet is configured to receive the exhaled breath. The pretreatment element is configured to receive the exhaled breath from the inlet and to condition a chemical characteristic of the exhaled breath. The sensing electrode is coupled to a chamber within the sensing apparatus. The chamber is configured to receive the pretreated exhaled breath from the pretreatment element. The sensing electrode is configured to detect a component of nitrogen oxide (NO_X) in the exhaled breath.

Claims

1. A sensing apparatus to measure nitric oxide (NO) in exhaled breath, the sensing apparatus comprising:

an inlet to receive the exhaled breath;

a pretreatment element to receive the exhaled breath from the inlet and to condition a chemical characteristic of the exhaled breath; and

a sensing electrode coupled to a chamber within the sensing apparatus, the chamber to receive the pretreated exhaled breath from the pretreatment element, the sensing electrode to detect a component of nitrogen oxide (NO_X) in the exhaled breath.

2. The sensing apparatus of claim 1, wherein the sensing electrode is further configured to detect NO in the exhaled breath.

3. The sensing apparatus of claim 1, further comprising another sensing electrode coupled to the chamber, the other sensing electrode to detect an oxygen component in the exhaled breath.

4. The sensing apparatus of claim 1, wherein the pretreatment element comprises an oxidation catalyst to oxidize hydrocarbons in the exhaled breath.

5. The sensing apparatus of claim 1, wherein the pretreatment element comprises an oxidation catalyst to oxidize ammonia in the exhaled breath to nitrogen and H₂O.

6. The sensing apparatus of claim 1, further comprising:

a receiver to receive the exhaled breath when the receiver is in close proximity to a source of the exhaled breath;

a conduit coupled between the receiver and the inlet, the conduit to direct the exhaled breath from the receiver to the inlet, the conduit comprising an interior surface material configured to deflect substantially all of the nitrogen oxide (NO_X) in the exhaled breath; and

an outlet to exhaust the exhaled breath from the sensing apparatus after the detection of the NO_X in the exhaled breath.

7. The sensing apparatus of claim 1, further comprising an electrode heater thermally coupled to the sensing electrode, the electrode heater to preheat the sensing electrode to within an operating temperature range of about 450-550°

C.

8. The sensing apparatus of claim 1, further comprising electronic circuitry coupled to the sensing electrode, the electronic circuitry to receive an electrode signal from the sensing electrode and to determine a level of NO in the exhaled breath according to the electrode signal from the sensing electrode.

9. The sensing apparatus of claim 8, wherein the sensing electrode is configured to detect nitrogen dioxide (NO₂) received from the pretreatment element, the electrode signal indicative of a level of the detected NO₂, the electronic circuitry further configured to convert the electrode signal indicative of the level of the detected NO₂ to an electronic signal indicative of the level of NO in the exhaled breath.

10. The sensing apparatus of claim 8, wherein the electronic circuitry comprises an electronic memory device to store a lookup table, the lookup table comprising a plurality of electrode signal values and a corresponding plurality of NO values.

11. The sensing apparatus of claim 8, further comprising a display device coupled to the electronic circuitry, the display device to display a message to a user, the message indicative of the level of NO in the exhaled breath.

12. The sensing apparatus of claim 11, wherein the message comprises a quantitative indicator or a qualitative indicator associated with the level of NO in the exhaled breath.

13. The sensing apparatus of claim 1, wherein the chamber comprises a volume of less than about 300 cubic centimeters.

14. The sensing apparatus of claim 1, wherein the chamber comprises a volume of less than about 50 cubic centimeters.

15. The sensing apparatus of claim 1, wherein the chamber comprises a volume of less than about 20 cubic centimeters.

16. The sensing apparatus of claim 1, wherein the chamber comprises a volume of less than about 5 cubic centimeters.

17. The sensing apparatus of claim 1, wherein the chamber comprises a volume of less than about 2 cubic centimeters.

18. The sensing apparatus of claim 1, further comprising a volume of less than about 300 cubic centimeters.

19. The sensing apparatus of claim 1, further comprising a volume of less than about 50 cubic centimeters.

20. The sensing apparatus of claim 1, further comprising a volume of less than about 20 cubic centimeters.

21. The sensing apparatus of claim 1, further comprising a volume of less than about 5 cubic centimeters.

22. The sensing apparatus of claim 1, further comprising a volume of less than about 2 cubic centimeters.

23. A method for measuring nitric oxide (NO) in exhaled breath, the method comprising:

receiving the exhaled breath;

pretreating a chemical characteristic of the exhaled breath;

conducting the pretreated exhaled breath to a sensing electrode; and

detecting a component of nitrogen oxide (NO_X) in the exhaled breath.

24. The method of claim 23, further comprising detecting the component of nitrogen oxide (NO_X) in the exhaled breath by detecting NO in the exhaled breath.

25. The method of claim 23, further comprising pretreating the chemical characteristic of the breath by oxidation of a component of the exhaled breath.

26. The method of claim 23, further comprising preheating the sensing electrode to within an operating temperature range of about 450-550°

C.

27. The method of claim 23, further comprising:

generating an electrode signal at the sensing electrode;

determining a level of NO in the exhaled breath based on the electrode signal; and

communicating to a user an indication of the level of NO in the exhaled breath.

28. A sensing apparatus to evaluate nitric oxide (NO) in exhaled breath, the sensing apparatus comprising:

means for conducting the exhaled breath to a chamber within the sensing apparatus;

means for generating an electrode signal in response to detection of a component of nitrogen oxide (NO_X) in the exhaled breath; and

means for determining a level of NO in the exhaled breath based on the electrode signal.

29. The sensing apparatus of claim 28, further comprising means for conveying a quantitative indicator to a user, the quantitative indicator indicative of the level of NO in the exhaled breath.

30. The sensing apparatus of claim 28, further comprising means for conveying a qualitative indicator to a user, the qualitative indicator indicative of the level of NO in the exhaled breath.