Integrated chemical indicator device

• US 20090023217A1
• Filed: 07/19/2007
• Published: 01/22/2009
• Est. Priority Date: 07/19/2007
• Status: Active Grant

• Current Assignee: Steris Inc (Steris Corporation)
• Original Assignee: Steris Inc (Steris Corporation)
• Inventors: Lacy, Stephen Michael, Tyers, Neil David
• Granted Patent: US 8,858,887 B2
• Time in Patent Office: Days
• US Class Current: 436/2
• CPC Class Codes: A61L 2/28 Devices for testing the effectiveness or completeness of sterilisation, e.g. indicators which change colour apparatus involving enzymes or microorganisms C12M1/34; methods involving enzymes or microorganisms C12Q1/00
• CPC Class Codes: G01N 31/005 investigating the presence of an element by oxidation G01N31/12 takes precedence
• CPC Class Codes: G01N 31/226 for investigating the degree of sterilisation
• CPC Class Codes: G01N 31/228 for peroxides

Abstract

A chemical indicator device for use in detecting exposure to an oxidizing agent, such as hydrogen peroxide, comprising a substrate or support upon which is disposed a chemical indicator composition (ink) for detecting an oxidizing agent, such as hydrogen peroxide. The chemical indicator composition further comprises an indicator dye that achieves a distinct range of different color changes with clear transitions between colors, upon exposure to different doses of the oxidizing agent, thus allowing for both a qualitative and semi-quantitative assessment of exposure to the agent.

Claims

1. A chemical indicator device comprising:

a. a substrate; and

b. a chemical indicator composition disposed upon the substrate, which comprises a dye for detecting an oxidizing agent,

wherein the dye achieves a distinct range of different color changes in response to different doses of the oxidizing agent.

2. The device according the claim 1, wherein the dye is a triphenyl methane dye.

3. The device according to claim 2, wherein the triphenyl methane dye is pararosaniline base.

4. The device according to claim 1, wherein the substrate comprises one or more polymeric materials, paper, woven fibers, non-woven fibers or a combination of two or more thereof.

5. The device according to claim 4, wherein the polymeric material is selected from the group consisting of polyesters, polystyrenes, polyolefins, polyamides, polymethacrylates, polyvinyl chlorides and mixtures thereof.

6. The device according to claim 5, wherein the polymeric material is a spun bonded polyolefin.

7. The device according to claim 1, wherein the chemical indicator composition further comprises binders, UV-protectants, anti-foaming agents, plasticizers, humectants, solvents, or a mixture of two or more thereof.

8. The device according to claim 1, wherein the oxidizing agent is hydrogen peroxide.

9. The device according to claim 1, wherein the dose of the oxidizing agent is determined by multiplying the concentration of the oxidizing agent by the time of exposure to the oxidizing agent.

10. A chemical indicator composition comprising:

a. a dye;

b. a binder;

c. a UV-protectant;

d. an anti-foaming agent;

e. optionally, a plasticizer or humectant; and

f. optionally, a solvent,

wherein the dye achieves a distinct range of different color changes in response to exposure to different doses of an oxidizing agent.

11. The chemical indicator composition according to claim 10, wherein the dye is selected from triphenyl methane dyes.

12. The chemical indicator composition according to claim 11, wherein the triphenyl methane dye is pararosaniline base.

13. The chemical indicator composition according to claim 10, wherein the color changes achieved may be calibrated to specific doses of the oxidizing agent so that a semi-quantitative assessment of exposure to the oxidizing agent can be made.

14. The chemical indicator composition according to claim 13, wherein the calibration of color change to dose of oxidizing agent provides a visual color chart for assessing semi-quantitative exposure to the oxidizing agent.

15. The chemical indicator composition according to claim 10, wherein the binder is selected from the group consisting of cellulosic materials, a polyamide, a polypropylene, a polyethylene, a polystyrene, polyethylene terephthalate, polyvinyl acetate, polyvinyl alcohol and mixtures thereof.

16. The chemical indicator composition according to claim 15, wherein the cellulosic material comprises nitrocellulose, hydroxymethyl cellulose or ethyl cellulose, or a mixture of two or more thereof.

17. The chemical indicator composition according to claim 10, wherein the solvent comprises water, an organic solvent, or a mixture thereof.

18. The chemical indicator composition according to claim 17, wherein the organic solvent is selected from the group consisting of alcohols, alkoxylated alcohols, ketones, esters, and mixtures thereof.

19. A chemical indicator composition uniformly disposed on a support, comprising pararosaniline base, wherein the composition achieves a distinct range of different colors, with clear transitions between colors, from the beginning of exposure to an oxidizing agent to the final or end point exposure to the agent.

20. The chemical indicator composition according to claim 19, wherein the composition is solvent free.

21. The chemical indicator composition according to claim 19, further comprising a binder, a UV-protectant, an anti-foaming agent, a plasticizer, a humectant, and at least one solvent.

22. The chemical indicator composition according to claim 21, wherein the solvent comprises water, an organic solvent, or a mixture thereof.

24. The chemical indicator composition according to claim 22, wherein the oxidizing agent is hydrogen peroxide.

23. A chemical indicator composition comprising pararosaniline base, which is disposed on a support, wherein the pararosaniline base achieves a distinct range of different colors upon exposure to different doses of an oxidizing agent.

25. A chemical indicator composition comprising:

a. pararosaniline base in amounts ranging from about 0.05 wt. % to about 10 wt. %;

b. a binder in amounts ranging from about 5 wt. % to about 90 wt. %.

c. a UV-protectant in amounts ranging from about 0.5 wt. % to about 5 wt. %; and

d. an anti-foaming agent in amounts ranging from about 0.1 wt. % to about 2 wt. %.

26. The chemical indicator composition according to claim 25, wherein the composition is solvent-free, and wherein the dye and any additional components are incorporated into suitable resins or waxes.

27. The chemical indicator composition according to claim 25, further comprising, optionally, a plasticizer, a humectant or a solvent.

28. The chemical indicator composition according to claim 25, wherein the binder comprises ethyl cellulose.

29. The chemical indicator composition according to claim 25, wherein the UV-protectant is a benzotriazole compound.

30. The chemical indicator composition according to claim 25, further comprising 2-methoxyethanol as a solvent.

31. The chemical indicator composition according to claim 25, further comprising 2-ethoxyethanol as a solvent.

32. The chemical indicator composition according to claim 25, wherein the composition is formulated to be suitable for UV-curing or electron beam curing.

33. The chemical indicator composition according to claim 32, wherein the dye and any additional components are combined with a suitable vinyl or acrylate monomer for UV-curing.

34. The chemical indicator composition according to claim 32, wherein the dye and any additional components are combined with an epoxy resin for electron beam curing.

35. The chemical indicator composition according to claim 25, wherein the composition is encapsulated in a transparent polymer to afford abrasion protection, to waterproof the ink and to enhance user safety.

36. The chemical indicator composition according to claim 35, wherein the transparent polymer comprises polymethacrylate, polyethylene, polyethylene terephthalate, cellophane, polypropylene or mixtures of two or more thereof.

37. A method of determining semi-quantitative exposure to an oxidizing agent comprising the steps of:

a. providing a chemical indicator device comprising a chemical indicator composition disposed on a support, wherein the composition comprises an indicator dye capable of achieving distinct color changes to different doses of the oxidizing agent;

b. placing the device into an environment wherein the device will be exposed to the oxidizing agent; and

c. comparing the color change achieved by the chemical indicator composition upon exposure to the oxidizing agent to a pre-calibrated color chart to assess a dose of oxidizing agent to which the chemical indicator composition was exposed.