US5942438A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Chemical indicator for oxidation-type sterilization processes using bleachable dyes
Assignee: Ethicon Inc
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Filing: 1997-11-07
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Granted: 1999-08-24
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Expires: 2017-11-07
Abstract
Abstract A method and apparatus for detecting exposure to an oxidation-type sterilant using a chemical indicator comprising bleachable dye is disclosed. Using the method and apparatus disclosed, a bleachable azo dye is incorporated with an anodized aluminum or chromate conversion coated surface and exposed to an oxidation-type sterilant, such as hydrogen peroxide, and inspected upon completion of the sterilization process for color change. If exposed to sterilant for an appropriate amount of time the bleachable dye changes color thereby indicating adequate sterilization. The surface incorporating bleachable dye may be made to change color after a predetermined number of exposures to a oxidation-type sterilant.
Inventors
- 👤 Patricia A. Antonoplos
- 👤 Henry K. Hui
- 👤 Alireza Ebrahim
- 👤 Leslie A. Feldman
- 👤 Nitu Kohli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:04
CPC Classifications
G; G01; G01N; G01N31/00; G01N31/22; A; A61; A61L; A61L2/00; A61L2/26; A61L2/28; C; C12; C12Q; C12Q1/00; C12Q1/02; C12Q1/22; G01N31/226
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
38 words
A method for indicating adequate exposure to an oxidative sterilant or disinfectant comprising: exposing a surface having a metallic azo dye thereon to an oxidative sterilant or disinfectant; and viewing said bleachable dye for a change in color.
Claim 2
Independent Claim
38 words
A method for indicating adequate exposure to an oxidative sterilant or disinfectant comprising: exposing a surface having a metallic azo dye thereon to an oxidative sterilant or disinfectant; and viewing said bleachable dye for a change in color.
Claim 3
Dependent Claim
21 words
The method of claim 1, wherein said exposing a surface comprises exposing a metallic surface to an oxidative sterilant or disinfectant.
Claim 4
Dependent Claim
14 words
The method of claim 1, wherein said exposing a surface comprises exposing anodized aluminum.
Claim 5
Dependent Claim
16 words
The method of claim 1, wherein said exposing a surface comprises exposing a chromate conversion coating.
Claim 6
Dependent Claim
30 words
The method of claim 1, wherein said exposing comprises providing oxidation-type sterilant in gaseous form to a chamber containing medical devices and a surface having a non-pH-sensitive, bleachable dye thereon.
Claim 7
Dependent Claim
26 words
The method of claim 1, wherein the step of exposing a non-pH-sensitive, bleachable dye comprises exposing aluminum bordeaux RL dye to an oxidative sterilant or disinfectant.
Claim 8
Dependent Claim
33 words
The method of claim 1, wherein the step of exposing the metallic azo dye to a oxidative sterilant or disinfectant comprises exposing bleachable dye to hydrogen peroxide, ozone, chlorine dioxide, and peracetic acid.
Claim 9
Dependent Claim
32 words
The method of claim 1, wherein the step of exposing a the metallic azo dye to a oxidative sterilant or disinfectant comprises exposing a bleachable dye to a sterilant in plasma form.
Claim 10
Dependent Claim
25 words
The method of claim 1, wherein said exposing comprises using a chemical indicator strip having a metallic azo dye thereon in an oxidative sterilization chamber.
Claim 11
Dependent Claim
41 words
The method of claim 1, wherein said exposing comprises placing a test pack with the metallic azo dye chemical indicator thereon in an oxidation-type sterilization chamber, said test pack configured to provide for gas flow into said test pack by diffusion.
Claim 12
Dependent Claim
43 words
The method of claim 1, wherein said exposing comprises placing a container in a sterilization chamber, said container having a cover, said cover secured to said container with a tamper-evident device, said tamper-evident device having said surface with the metallic azo dye thereon.
Claim 13
Dependent Claim
21 words
The method of claim 1, wherein said change in color is not apparent until a plurality of exposing steps are conducted.
Claim 14
Dependent Claim
23 words
The method of claim 1, wherein said exposing a surface comprises exposing a flexible medium having the metallic azo dye and adhesive thereon.
Claim 15
Dependent Claim
28 words
The method of claim 1, wherein said exposing comprises placing a self-contained biological indicator having a surface with the metallic azo dye thereon in an oxidative sterilization chamber.
Claim 16
Dependent Claim
27 words
The method of claim 14, wherein said surface having the metallic azo dye thereon comprises a generally flat disc on the cap of said self-contained biological indicator.
Claim 17
Independent Claim
74 words
A method for determining if a device has been exposed to an oxidation-type sterilization process a predetermined number of times comprising: exposing a device with a surface having a metallic azo dye thereon to an oxidation-type sterilant, said dye configured to change color after a predetermined number of oxidation-type sterilization processes; viewing said surface after said exposing to determine if the color of said dye has changed from the original color of said dye.
Claim 18
Independent Claim
74 words
A method for determining if a device has been exposed to an oxidation-type sterilization process a predetermined number of times comprising: exposing a device with a surface having a metallic azo dye thereon to an oxidation-type sterilant, said dye configured to change color after a predetermined number of oxidation-type sterilization processes; viewing said surface after said exposing to determine if the color of said dye has changed from the original color of said dye.
Claim 19
Dependent Claim
37 words
The method of claim 16, wherein said exposing comprises exposing the surface with the metallic azo dye thereon in contact with an oxidation-type sterilant, said surface with the metallic azo dye thereon residing on an aluminum substrate.
Claim 20
Dependent Claim
37 words
The method of claim 16, wherein said exposing comprises exposing a device with an anodized aluminum surface having the dye thereon to a sterilant, said dye configured to change color after a predetermined number of sterilization processes.
Claim 21
Dependent Claim
37 words
The method of claim 16, wherein said exposing comprises exposing a device with a chromate conversion coated surface having dye thereon to a sterilant, said dye configured to change color after a predetermined number of sterilization processes.
Claim 22
Dependent Claim
17 words
The chemical indicator of claim 16, wherein said surface comprises of polyester, polystyrene, polyethylene, polypropylene, and cellulosics.
Claim 23
Dependent Claim
17 words
The method of claim 16, wherein said surface comprises a flexible medium having adhesive on one side.
Claim 24
Dependent Claim
14 words
The method of claim 16, wherein said surface comprises part of a tamper-evident device.
Claim 25
Dependent Claim
24 words
The method of claim 16, wherein said azo dye is configured to change color after a predetermined number of exposures to an oxidation-type sterilant.
Claim 26
Dependent Claim
30 words
The method of claim 23, wherein said predetermined number of exposures comprises the number of times a medical device may be used before the warranty of said medical device expires.
Claim 27
Independent Claim
35 words
An apparatus for determining exposure to an oxidation-type sterilization comprising: metallic surface means for containing a metallic azo dye thereon; the metallic azo dye on said surface means for indicating exposure to an oxidation-type sterilant.
Claim 28
Independent Claim
35 words
An apparatus for determining exposure to an oxidation-type sterilization comprising: metallic surface means for containing a metallic azo dye thereon; the metallic azo dye on said surface means for indicating exposure to an oxidation-type sterilant.
Claim 29
Dependent Claim
13 words
The apparatus of claim 25, wherein said indicator means is generally pH nonreactive.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-08-23 | 2003-02-22 | 2003-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-08-23 | 2007-02-22 | 2007-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-08-23 | 2011-02-22 | 2011-08-24 | $7700.00 | Window Closed / Lapsed |