CALIBRATION CARD FOR PHOTOLUMINESCENT OXYGEN SENSORS

• US 20100116017A1
• Filed: 12/08/2009
• Published: 05/13/2010
• Est. Priority Date: 11/07/2008
• Status: Active Grant

• Current Assignee: Agilent Technologies, Inc.
• Original Assignee: MOCON, Inc. (Ametek Incorporated)
• Inventors: Mayer, Daniel W., Papkovsky, Dmitri Boris
• Granted Patent: US 8,093,055 B2
• Time in Patent Office: Days
• US Class Current: 73/1.60
• CPC Class Codes: G01N 2021/6441 with two or more labels
• CPC Class Codes: G01N 21/274 Calibration, base line adjustment, drift correction
• CPC Class Codes: G01N 21/278 Constitution of standards
• CPC Class Codes: Y10T 436/10 Composition for standardization, calibration, simulation, stabilization, preparation or preservation; processes of use in preparation for chemical testing
• CPC Class Codes: Y10T 436/100833 Simulative of a gaseous composition
• CPC Class Codes: Y10T 436/20 Oxygen containing
• CPC Class Codes: Y10T 436/207497 Molecular oxygen
• CPC Class Codes: Y10T 436/25875 Gaseous sample or with change of physical state

Abstract

A calibration card and method of manufacturing and using the card to calibrate an analytical instrument capable of reading a photoluminescent oxygen probe. The card includes at least (a) a first mass of a first solid state composition comprising an oxygen-sensitive photoluminescent dye that is the same as the probe dye, embedded within an oxygen-permeable carrier matrix that is the same as the probe carrier matrix, wherein the first composition has a first sensitivity to oxygen, and, (b) a second mass of a second solid state composition comprising an oxygen-sensitive photoluminescent dye that is the same as the dye in the first mass, embedded within a carrier matrix that is different from the carrier matrix in the first mass, wherein the second composition has a known second sensitivity to oxygen that is less than the first sensitivity to oxygen.

Claims

1. A calibration card for use in calibrating an analytical instrument capable of reading a photoluminescent oxygen probe from which the concentration of oxygen in a sample communicating with the probe can be determined, wherein the probe comprises an oxygen-sensitive photoluminescent dye embedded within an oxygen-permeable carrier matrix, comprising:

(a) a first mass of a first solid state composition comprising an oxygen-sensitive photoluminescent dye that is the same as the probe dye, embedded within an oxygen-permeable carrier matrix that is the same as the probe carrier matrix, wherein the first composition has a first sensitivity to oxygen, and

(b) a second mass of a second solid state composition comprising an oxygen-sensitive photoluminescent dye that is the same as the dye in the first mass, embedded within a carrier matrix that is different from the carrier matrix in the first mass, wherein the second composition has a known second sensitivity to oxygen that is less than the first sensitivity to oxygen.

2. The calibration card of claim 1 wherein the carrier matrix in the second mass is an oxygen impermeable carrier matrix.

3. The calibration card of claim 1 wherein both the first and second masses are in fluid communication with the atmosphere.

4. The calibration card of claim 1 wherein the oxygen-sensitive photoluminescent dye is a transition metal complex.

5. The calibration card of claim 4 wherein the transition metal complex is selected from the group consisting of a ruthenium bipyridyl, a ruthenium diphenylphenanotroline, a platinum porphyrin, a palladium porphyrin, a phosphorescent complex of a tetrabenzoporphyrin, a chlorin, a porphyrin-ketone, an aza-porphyrin and a long-decay luminescent complex of iridium(III) or osmium(II).

6. The calibration card of claim 1 wherein the matrix component of the first composition is highly oxygen permeable.

7. The calibration card of claim 1 wherein the matrix component of the first composition is selected from the group consisting of silicone, polystryrene, polycarbonate, and polysulfone.

8. The calibration card of claim 3 wherein the matrix component of the second composition is selected from the group consisting of polyvinyl chloride, polymethylmethacrylate, a polyvinylidine chloride-polyvinyl chloride copolymer, a polyvinylidene chloride-acrylonitrile copolymer, and polyethylene vinyl alcohol.

9. The calibration card of claim 1 wherein the second sensitivity to oxygen is at least 10 times less than the first sensitivity to oxygen.

10. The calibration card of claim 3 wherein the second sensitivity to oxygen is at least 100 times less than the first sensitivity to oxygen.

11. The calibration card of claim 1, wherein the card has a length of about 4 to 20 cm, a width of about 4 to 20 cm, and a thickness of less than 1 cm.

12. The calibration card of claim 10, wherein the card has a length of about 6 to 10 cm, a width of about 4 to 8 cm, and a thickness of less than 3 mm.

13. The calibration card of claim 1 wherein at least the second mass is applied as a coating onto an oxygen barrier support layer.

14. The calibration card of claim 13 wherein the oxygen barrier support layer is selected from the group consisting of polyethylene terephthalate, polyvinyl chloride, polyethylene and polypropylene.

15. The calibration card of claim 14 wherein the oxygen barrier support layer is biaxially oriented polyethylene terephthalate.

16. The calibration card of claim 13 wherein the first and second masses are covered by a transparent cover layer.

17. The calibration card of claim 16 wherein the transparent cover layer is at least one of a highly oxygen permeable or a perforated film.

18. The calibration card of claim 1 wherein the photoluminescence intensity signal from the second composition is within an order of magnitude of the photoluminescence intensity signal of the probe.

19. The calibration card of claim 1, wherein the card contains (i) first indicia tagging the first mass to a calibration value of a probe exposed to an environmental concentration of oxygen, and (ii) second indicia tagging the second mass to a calibration value of a probe exposed to a defined concentration of oxygen that is less than an environmental concentration of oxygen.

20. The calibration card of claim 19, wherein the first indicia comprises at least a numerical value of 21% and the second indicia comprises at least a numerical value that is less than 1%.

21. The calibration card of claim 20, wherein the second indicia is 0%.

22. A method of calibrating an analytical instrument having a calibration mode and capable of reading a photoluminescent oxygen probe or plurality of photoluminescent oxygen probes from which the concentration of oxygen in a sample or set of samples communicating with the probe can be determined, comprising the steps of:

(a) obtaining a calibration card according to claim 1,

(b) exposing the first and second masses on the calibration card to a medium having a known concentration of oxygen,

(c) setting the analytical instrument to calibration mode,

(d) taking a reading from the first mass with the analytical instrument,

(e) correlating the value of the reading to the known oxygen concentration to which the calibration card is exposed,

(f) taking a reading from the second mass with the analytical instrument, and

(g) correlating the value of the reading to an oxygen concentration based upon the known second oxygen sensitivity of the second mass.

23. A method of calibrating an analytical instrument having a calibration mode that is capable of reading a photoluminescent probe from which the concentration of oxygen in the sample communicating with the probe can be determined, comprising the steps of:

(a) obtaining a calibration card according to claim 9,

(b) exposing the first and second masses on the calibration card to the atmosphere,

(c) setting the analytical instrument to calibration mode,

(d) taking a reading from the first mass with the analytical instrument,

(e) correlating the value of the reading to the known oxygen concentration of the atmosphere,

(f) taking a reading from the second mass with the analytical instrument, and

(g) correlating the value of the reading to an oxygen concentration based upon the known second oxygen sensitivity of the second mass.

24. The method of claim 22 wherein the steps of taking a reading from the first and second masses are performed in a predetermined sequence.

25. The method of claim 23 further comprising the step of providing the analytical instrument with data indicating which of the masses on the calibration card was read first.

26. The method of claim 22 further comprising the step of providing the analytical instrument with data indicating the oxygen concentration of the sample to which the first mass is exposed.

27. The method of claim 23 wherein readings and correlations are based upon photoluminescence lifetime.

28. A method of manufacturing the calibration card according to claim 1, which includes at least the steps of:

(a) preparing a first coating cocktail which contains the oxygen-sensitive photoluminescent dye of the first mass and the oxygen-permeable carrier matrix of the first mass in an organic solvent,

(b) applying the first cocktail to the first major surface of a support material,

(c) allowing the applied first cocktail to dry, whereby a solid-state thin film coating of the first mass is formed on the support,

(d) preparing a second coating cocktail which contains the oxygen-sensitive photoluminescent dye of the second mass and the oxygen-impermeable carrier matrix of the second mass in an organic solvent,

(e) applying the second cocktail to the first major surface of a support material,

(f) allowing the applied second cocktail to dry, whereby a solid-state thin film coating of the second mass is formed on the support, and

(g) laminating the thin film coatings of the first and second masses to a stiff structural layer at spaced locations on a major surface of the structural layer so as to permit independent readings to be taken from each mass by the analytical instrument.

29. The method of claim 28 wherein the first and second cocktails are applied to the same support.

30. The method of claim 28 wherein the stiff structural layer is selected from the group consisting of card stock, paperboard and rigid plastic films.