Hydroxyl radical detection

• US 20080003687A1
• Filed: 06/28/2006
• Published: 01/03/2008
• Est. Priority Date: 06/28/2006
• Status: Active Grant

• Current Assignee: The Board of Trustees of Michigan State University (Michigan State University)
• Original Assignee: The Board of Trustees of Michigan State University (Michigan State University)
• Inventors: Masten, Susan J., Trosko, James, Satoh, Andrea Yuki
• Granted Patent: US 7,939,340 B2
• Time in Patent Office: Days
• US Class Current: 436/169
• CPC Class Codes: G01N 21/78 producing a change of colour
• CPC Class Codes: Y10T 436/203332 Hydroxyl containing

Abstract

The invention relates to compositions, kits and methods used in hydroxyl radical detection. In some embodiments, the invention relates to compositions comprising a dye preferably methylene blue immobilized on a substrate. In additional embodiments, the invention relates methods of correlating color changes of a dye to the presence or absence of hydroxyl radicals. In some embodiments, the invention relates to a methylene blue dye containing test strip and its use in a method for detecting the presence of hydroxyl radicals.

Claims

1. A method of determining the presence of hydroxyl radicals in a sample comprising:

i) providing;

a) a liquid sample and

b) a bisaminophenothiazine dye immobilized on a substrate, said substrate having a color; and

ii) contacting said bisaminophenothiazine dye with said sample under conditions such that said color of said substrate changes, thereby indicating the presence of hydroxyl radicals in said sample.

2. The method of claim 1, wherein said bisaminophenothiazine dye is the compound 3,7-bis(dimethylamino)phenothiazine-5-ium chloride.

3. The method of claim 1, wherein said bisaminophenothiazine dye, prior to step (ii), is dried on said substrate.

4. The method of claim 1, wherein said substrate comprises one or more hydrophobic barriers.

5. The method claim 1, wherein said sample contains hydrogen peroxide.

6. A method of determining the presence of hydroxyl radicals in a sample comprising:

i) providing;

a) a liquid sample and

b) a dye stable to a solution of hydrogen peroxide immobilized on a substrate, said substrate having a color; and

ii) contacting said dye with said sample under conditions such that said color of said substrate changes, thereby indicating the presence of hydroxyl radicals in said sample.

7. The method of claim 6, wherein said dye is a bisaminophenothiazine dye.

8. The method of claim 7, wherein said bisaminophenothiazine dye, prior to step (ii), is dried on said substrate.

9. The method of claim 6, wherein said substrate is paper.

10. The method of claim 6, wherein said substrate comprises one or more hydrophobic barriers.

11. The method of claim 6, wherein said sample contains hydrogen peroxide.

12. A method of verifying hydroxyl radical quenching in a solution comprising:

a) providing,

i) a solution containing a hydroxyl radical and hydrogen peroxide;

ii) a quenching reagent of hydroxyl radicals; and

iii) a substrate comprising a dye;

b) mixing said quenching reagent and said solution containing said hydroxyl radical under conditions such that a mixed solution is formed;

c) separating a sample of said mixed solution;

d) contacting said sample with said substrate comprising a dye; and

e) correlating said color of said dye to the existence of hydroxyl radicals in said mixed solution.

13. The method of claim 12, wherein steps b), c), d), and e) are each done more than once.

14. The method of claim 12, wherein said dye is a bisaminophenothiazine dye.

15. The method of claim 14, wherein said bisaminophenothiazine dye is the compound 3,7-bis(dimethylamino)phenothiazine-5-ium chloride.

16. The method of claim 12, wherein said hydroxyl radical quenching reagent is Na₂SO₃.

17. The method of claim 12, wherein correlating said color is visually observing substantial discoloration of said test area as an indication of the presence of hydroxyl radicals.

18. The method of claim 12, wherein correlating said color is visually observing substantially no discoloration of said test area as an indication of the absence of hydroxyl radicals.

19. A kit comprising a substrate immobilized with a bisaminophenothiazine dye and a liquid transferring mechanism.

20. The kit of claim 19, wherein said liquid transferring mechanism is a capillary tube.