NON INVASIVE GAS ANALYSIS

• US 20120148452A1
• Filed: 06/03/2010
• Published: 06/14/2012
• Est. Priority Date: 06/04/2009
• Status: Abandoned Application

• Current Assignee: Haemaflow Limited
• Original Assignee: Haemaflow Limited
• Inventors: Johns, William Richard, Phillips, Richard, Ricketts, Stephen Robert, Rogers, Dale, Brown, Stephen Warwick James, Douglas, Peter
• Application Number:
  US13/375,930
• Publication Number:
  US 20120148452A1
• Time in Patent Office: Days
• US Class Current: 422/86
• CPC Class Codes: A61B 5/14556 by fluorescence A61B5/14555 takes precedence
• CPC Class Codes: A61M 1/1698 Blood oxygenators with or without heat-exchangers intracorporal A61M1/1678; manufacturing of membranes therefor B01D67/00; semi-permeable membranes for separation processes characterised by their properties B01D69/00; semi-permeable membranes characterised by their material B01D71/00
• CPC Class Codes: A61M 2205/3306 Optical measuring means
• CPC Class Codes: G01N 21/78 producing a change of colour
• CPC Class Codes: G01N 33/4925 measuring blood gas content, e.g. O2, CO2 , HCO3

Abstract

A sensing device is provided. The device comprises a gas permeable member, a sensing member and optical means.

The gas permeable member is arranged to receive gas from a substance to be tested. The sensing member is located adjacent to the gas permeable member and comprises a sensing substance. A property of the sensing substance is modified when it is brought into contact with the gas received by the gas permeable member.

The optical means comprises a light source which is arranged to irradiate the sensing substance together with a first sensor which is configured to detect a change in the aforementioned property of the sensing substance.

Claims

1. A sensing device comprising:

a gas permeable member arranged to receive gas from a substance to be tested;

a sensing member, located adjacent to the gas permeable member comprising a sensing substance, a property of which substance is modified when brought into contact with the received gas; and

optical means comprising;

a light source arranged to irradiate the sensing substance;

a first sensor configured to detect a change in the property of the sensing substance.

2. A device according to claim 1, wherein the property is intensity of light and the first sensor is configured to detect a change in the intensity of light emitted or absorbed at a characteristic wavelength.

3. A device according to claim 1, comprising transmitting means for transmitting a signal indicative of the property of the sensing substance to analysing means.

4. A device according to claim 3, wherein the analysing means is configured to calculate a parameter of the substance to be tested from the detected property of the sensing substance.

5. A device according to claim 4, wherein the parameter is partial pressure of the gas present in the substance to be tested.

6. A device according to claim 3, comprising the analysing means and wherein the analysing means comprises receiving means for receiving the signal.

7. A device according to claim 6, wherein the analysing means comprises storage means for recording and storing the received signal or the calculated parameter.

8. A device according to claim 1, wherein the gas permeable member is substantially opaque.

9. A device according to claim 1, wherein the gas permeable member comprises an opaque membrane.

10. A device according to claim 1, wherein the sensing substance is a dye sensitive to a specific gas.

11. A device according to claim 1, wherein the optical means comprises a first filter, associated with the first sensor.

12. A device according to claim 1, wherein the optical means comprises a second sensor.

13. A device according to claim 12, wherein the optical means comprises a second filter, associated with the second sensor.

14. A device according to claim 1, wherein the light source is a light emitting diode (LED).

15. A device according to claim 1, wherein the gas permeable member and the sensing member in combination are configured to receive a volume of gas less than 3 μ

l.

16. A device according to claim 15, wherein the volume of gas is less than 0.2 μ

l.

17. A device according to claim 16, wherein the volume of gas is less than 0.01 μ

l.

18. A device according to claim 1, wherein the gas to be detected is oxygen.

19. A device according to claim 18, wherein the light source is an ultraviolet LED.

20. A device according to claim 18, wherein the sensing substance is platinum (II) octaethylporphyrin.

21. A device according to claim 1, wherein the gas to be detected is carbon dioxide.

22. A device according to claim 21, wherein the light source is a blue LED.

23. A device according to claim 21, wherein the sensing substance is 8-hydoxypyrene-1,3,6 trisulfonic acid.

24. A blood/air mass exchange apparatus in combination with a sensing device according to claim 1.

25. Apparatus according to claim 24, wherein the, or each, sensing device is associated with a respective one of the group of a blood inlet of the apparatus, a blood outlet of the apparatus, an air inlet of the apparatus and an air outlet of the apparatus.

26. Apparatus according to claim 25, comprising means for monitoring a fluid flow in to and out of the apparatus.

27. Apparatus according to claim 26, wherein the means for monitoring is configured to monitor a balance of mass flow on a substantially continuous basis.

28. A device according to claim 1 comprising a housing member defining a cavity therewithin, the cavity being closed by the sensing member, the optical means being mounted within the cavity.

29. A device according to claim 28, wherein the cavity comprises a transparent, substantially incompressible medium.

30. A device according to claim 29, wherein the transparent medium is one of the group of an oil and a resin.

31. A deep ocean apparatus, comprising a device according to claim 29.

32. A device according to claim 1 wherein said device comprising an adhesive patch suitable for adhering to human or animal skin.

33. (canceled)