PH indicator device and formulation

• US 10,288,590 B2
• Filed: 11/06/2017
• Issued: 05/14/2019
• Est. Priority Date: 10/08/2013
• Status: Active Grant

• Current Assignee: Smith & Nephew PLC
• Original Assignee: Smith & Nephew PLC
• Inventors: Hammond, Victoria Jody, Hicks, John Kenneth
• Primary Examiner(s): Alexander, Lyle
• Assistant Examiner(s): Kilpatrick, Bryan
• Application Number:
  US15/804,748
• Publication Number:
  US 20180196021A1
• Time in Patent Office: 554 Days
• CPC Class Codes: A61B 5/14539 for measuring pH
• CPC Class Codes: A61F 2013/427 pH indicator
• CPC Class Codes: G01N 21/80 Indicating pH value
• CPC Class Codes: G01N 27/4165 for pH meters
• CPC Class Codes: G01N 31/221 for investigating pH value

Abstract

Disclosed herein are devices and methods for determining the pH of fluid. Example devices include a device comprising a surface configured to contact the fluid and a pH indicator covalently bound thereto, wherein the pH indicator has a first color prior to contact with the fluid and changes color as a function of the pH of the fluid.

Claims

1. An article of manufacture, comprising:

a fluid-contacting surface, wherein the article of manufacture further comprises a gel positioned on the fluid-contacting surface, the gel configured to contact the fluid, the gel comprising a pH indicator comprising 2-[(4-(2-hydroxyethylsulfonyl)-phenyl)diazenyl]-4-methylphenol and 4-[4-(2-hydroxyethylsulphonyl)-phenylazo]-2,6-dimethoxy phenol in about a 2;

1 ratio.

2. The article of claim 1, wherein the gel is an adhesive.

3. The article of claim 1, further comprising a conduit configured to direct fluid to the pH indicator.

4. The article of claim 1, wherein the fluid contacting surface comprises a film.

5. The article of claim 1, wherein the fluid contacting surface comprises an absorbent pad.

6. The article of claim 1, wherein the fluid contacting surface comprises a mesh.

7. The article of claim 1, wherein the article is configured to indicate food spoilage.

8. The article of claim 7, wherein the article is configured to be positioned on a food package.

9. The article of claim 1, wherein the article is configured to be placed in a wound.

10. The article of claim 1, wherein the fluid-contacting surface is a coating, the coating configured to be placed on a packaging material.

11. The article of claim 1, wherein the article is configured to monitor drug release.

12. The article according to claim 1, wherein the colour change in the pH indicator is detectable at a 0.1 unit interval change in pH.

13. The article according to claim 12, wherein the colour change in the pH indicator is detectable between about pH 5 and about pH 10.

14. The article according to claim 13, wherein the colour change in the pH indicator is detectable between about pH 5.5 and about pH 9.5.

15. The article according to claim 13, wherein the colour change in the pH indicator is detectable between about pH 6.5 and 9.5.

16. The article according to claim 1, wherein the article comprises a cellulosic material.

17. The article according to claim 1, wherein the article comprises a peripheral edge, the pH indicator positioned on the peripheral edge.