Hydrogen peroxide indicator employing enzyme and dye

• US 6,635,439 B2
• Filed: 12/21/2000
• Issued: 10/21/2003
• Est. Priority Date: 12/21/2000
• Status: Expired due to Term

• Current Assignee: Ethicon Incorporated (Johnson & Johnson)
• Original Assignee: Ethicon Incorporated (Johnson & Johnson)
• Inventors: Morrison, Todd, Thralls, Veronica V., Jurik, Franklin A.
• Primary Examiner(s): Weber, Jon P.
• Application Number:
  US09/745,212
• Publication Number:
  US 20020119508A1
• Time in Patent Office: 1,034 Days
• Field of Search: 435/27, 435/28, 435/25
• US Class Current: 435/28
• 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: C12Q 1/22 Testing for sterility conditions
• CPC Class Codes: C12Q 1/28 involving peroxidase
• CPC Class Codes: G01N 21/8483 Investigating reagent band test-element handling not specific to a test method G01N33/4875; analytical elements specific to chemical analysis of biological material G01N33/52; autometer with reagent band G01N35/04
• CPC Class Codes: G01N 31/228 for peroxides

Abstract

A method for determining exposure of a test sample to hydrogen peroxide in an atmosphere includes placing a substrate into the atmosphere, contacting the substrate with the hydrogen peroxide, reacting the hydrogen peroxide with a dye intermediate to produce a chromophore indicative of the integrated exposure of hydrogen peroxide in the atmosphere; and correlating the chromophore to the integrated exposure of hydrogen peroxide in the atmosphere. The dye intermediate may be a dye-couple of 3-methyl-2-benzothiazolinone hydrazone hydrochloride (MBTH) and 3-dimethylaminobenzoic acid (DMAB). The intensity of the chromophore is indicative of an integrated hydrogen peroxide exposure.

Claims

1. A method for detecting the integrated exposure of an item to hydrogen peroxide in a sterilization chamber having an atmosphere, the method comprising the steps of:

placing the item into the chamber;

placing a substrate capable of absorbing hydrogen peroxide in the chamber;

contacting the item and the substrate with the hydrogen peroxide;

hydrating the substrate in the presence of a thickening agent;

on the substrate, reacting the hydrogen peroxide with a dye intermediate and an enzyme capable of reacting with hydrogen peroxide to produce a chromophore indicative of the integrated exposure of hydrogen peroxide in the atmosphere; and

correlating the chromophore to the integrated exposure of hydrogen peroxide in the atmosphere.

2. A method according to claim 1 wherein the dye intermediate comprises a dye-couple of 3-methyl-2-benzothiazolinone hydrazone hydrochloride (MBTH) and 3-dimethylaminobenzoic acid (DMAB).

3. A method according to claim 1 wherein the enzyme is peroxidase.

4. A method according to claim 1 wherein the dye intermediate comprises an oxygen acceptor.

5. A method according to claim 4 wherein the oxygen acceptor is selected from the group consisting of:

O-dianisidine;

O-toluidine;

O-tolidine;

Benzidine;

2,2′

-Azinodi-(3-ethylbenzthiazoline sulphonic acid-(6));

3-Methyl-2-benzothiazolinone hydrazone plus N,N-dimethylaniline;

Phenyl plus 4-aminophenazone;

Sulfonated 2,4-dichloro-phenol plus 4-aminophenazone;

3-Methyl-2-benzothiazolinone hydrazone plus 3-(dimethylamino)benzoic acid;

2-Methoxy-4-allyl phenol; and

4-Aminoantipyrene-dimethylaniline.

6. A method according to claim 1 wherein the substrate is a porous receiver.

7. A method according to claim 1 wherein the step of correlating the chromophore to the integrated exposure of hydrogen peroxide in the atmosphere comprises reading the chromophore with a spectrophotometer.

8. A method according to claim 1 wherein the step of correlating the chromophore to the integrated exposure of hydrogen peroxide in the atmosphere comprises comparing the chromophore with a color chart.

9. A method according to claim 1 wherein the dye intermediate is on the substrate before contacting the substrate with the hydrogen peroxide.

10. A method according to claim 1 wherein the dye intermediate is added onto the substrate after contacting the substrate with the hydrogen peroxide.

11. A method according to claim 1 wherein the dye intermediate has a first color.

12. A method according to claim 1 wherein the chromophore is the appearance of a second color.

13. A method according to claim 1 wherein the chromophore is the disappearance of the first color.

14. A method according to claim 1 wherein the enzyme is on the substrate before contacting the substrate with the hydrogen peroxide.

15. A method according to claim 1 wherein the enzyme is added onto the substrate after contacting the substrate with the hydrogen peroxide.

16. A method according to claim 1 wherein the thickening agent comprises white glue.