Controlled activation pH sensor

• US 8,262,878 B2
• Filed: 07/25/2007
• Issued: 09/11/2012
• Est. Priority Date: 07/25/2007
• Status: Active Grant

• Current Assignee: Sierra Medical Technology
• Original Assignee: Sierra Medical Technology
• Inventors: Wolf, Erich H., Bankert, Charles, Tsukashima, Ross, Custodio, Elmer
• Primary Examiner(s): Ball, J. Christopher
• Application Number:
  US11/881,021
• Publication Number:
  US 20090026078A1
• Time in Patent Office: 1,875 Days
• Field of Search: 205/787.5, 204/402, 204/416, 204/433, 600/529, 600/361, 600/547, 436/68
• US Class Current: 204/433
• CPC Class Codes: G01N 27/4035 Combination of a single ion-sensing electrode and a single reference electrode G01N27/406 and G01N27/413 take precedence

Abstract

The present invention pertains to a means of combining and configuring specific hydrophilic and dielectric materials in such a way as to allow an antimony/reference electrode pH sensor to be packaged and stored dry yet become fully hydrated to an activated state after exposure to aqueous liquids. The sensor is packaged and stored dry to maintain component stability and minimize component degradation. When the user removes the sensor from the package and the sensor tip is submerged in a hydration (ion conduction) media or solution, the hydrophilic coating along with the impregnated reference wick, absorb the fluid to create an electrolytic gel inside the reference wick, which activates the pH sensor.

Claims

1. A controlled activation sensor assembly for monitoring pH or other constituents, comprising:

a tubular member having a proximal end and a distal end, said tubular member comprised of an outer tubular member and one or more inner tubular members, said outer tubular member co-linearly or coaxially enclosing one or more inner tubular members, said outer tubular member having a terminal end;

a dry state wick material enclosed within a first inner tubular member, said dry state wick material including a dry matrix of hygroscopic and/or hydrophilic materials, said dry state wick material acting as a capillary tube that facilitates liquid flow;

a dry state reference electrode, said dry state reference electrode comprising a silver wire terminally coated with a silver chloride coating, said dry state reference electrode enclosed in a proximal position within said dry state wick material and within said first inner tubular member,

an expansion plug located proximal to said dry state wick and within said inner tubular member, said expansion plug designed to regulate the amount of liquid absorbed and control the electrolyte concentration;

one or more sodium chloride rods that are positioned in close proximity to the reference wick;

an antimony metal segment enclosed within said outer tubular member, said outer tubular member electrically isolates said antimony metal segment from said reference electrode;

said tubular member, said dry state wick, said dry state reference electrode, and said antimony metal forming a non-active sensor; and

said non-activated sensor designed to become activated upon exposing said distal end to a hydration solution whereby said hydration solution is transported proximally to become retained within a portion of said wick material.

2. The sensor as recited in claim 1, wherein said dry state wick material is selected from the group consisting of fibrous polymeric meshes of polyester, polyimide, polyethylene, polypropylene, polyvinyl chloride, polystyrene, ABS, nylon, delrin, or polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), polysaccharide, or any combinations thereof.

3. The sensor as recited in claim 1, wherein said dry state wick is a porous material selected from the group consisting of porous ceramic, metallic or polymeric materials.

4. The sensor as recited in claim 1, further comprising one or more sodium chloride rods located proximal to said dry state wick and within said inner tubular member.

5. The sensor as recited in claim 1, further comprising an expansion plug located proximal to said dry state wick and within said inner tubular member.

6. The sensor as recited in claim 1, wherein said hydration solution consists of an aqueous, another polar solution, or a conduction fluid which may contain sodium chloride, potassium chloride or other conductive ion formation materials.

7. The sensor as recited in claim 1, wherein said dry state wick comprises an electrolyte/water based gel when activated.

8. The sensor as recited in claim 1, wherein said dry state wick comprises a conductive polymer when activated.

9. The sensor as recited in claim 1, wherein said dry state reference element comprises a silver element having a silver chloride coating.

10. The sensor as recited in claim 1, further comprising a hygroscopic and/or hydrophilic coating adhered to said distal end.

11. The sensor as recited in claim 1, further comprising an electrical and display means which is in communication with the sensor and processes information obtained from said sensor for presenting a pH reading.

12. A controlled activation sensor for monitoring pH or other constituents, comprising:

an outer tubular member and an inner tubular member, said outer tubular member co-linearly or coaxially enclosing an inner tubular member, said outer tubular member having a terminal end;

a dry state wick material located within said inner tubular member, said wick material impregnated with a dry matrix of hydroscopic and/or hydrophilic materials, said wick material including one or more micro-channels, said dry state wick material acting as a capillary tube that facilitates liquid flow;

a dry state reference electrode, said dry state reference electrode comprising a silver wire terminally coated with silver chloride coating, said dry state reference electrode enclosed in a proximal position within said dry state wick material and within said first inner tubular member;

one or more sodium chloride rods that are positioned in close proximity to the reference wick;

an antimony metal segment enclosed within said outer tubular member, said outer tubular member electrically isolates said antimony metal segment from said reference electrode;

an expansion plug located proximal to said dry state wick and within said inner tubular member, said expansion plug designed to regulate the amount of liquid absorbed and control the electrolyte concentration;

said controlled activation sensor becoming activated upon exposing said terminal end to a hydration solution whereby said solution facilitates said solution to proceed proximally up said wick and one or more micro-channels to become entrained within said wick material; and

said sensor assembly being of a small mass such that it functions to cool efficiently and subsequently condenses humid gases in close proximity to said sensor to form a liquid on said terminal end.

13. The sensor as recited in claim 12, wherein said dry state wick material is selected from the group consisting of fibrous polymeric meshes of polyester, polyimide, polyethylene, polypropylene, polyvinyl chloride, polystyrene, ABS, nylon, delrin, or polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), polysaccharide, or any combinations thereof.

14. The sensor as recited in claim 12, wherein said dry state wick is a porous material selected from the group consisting of porous ceramic, metallic or polymeric materials.

15. The sensor as recited in claim 12, further comprising one or more sodium chloride rods located proximal to said dry state wick and within said inner tubular member.

16. The sensor as recited in claim 12, further comprising an expansion plug located proximal to said dry state wick and within said inner tubular member.

17. The sensor as recited in claim 12, wherein said hydration solution consists of an aqueous, another polar solution, or a conduction fluid which may contain sodium chloride, potassium chloride or other conductive ion formation materials.

18. The sensor as recited in claim 12, wherein said dry state wick comprises an electrolyte/water based gel when activated.

19. The sensor as recited in claim 12, wherein said dry state wick comprises a conductive polymer when activated.

20. The sensor as recited in claim 12, wherein said dry state reference element comprises a silver element having a silver chloride coating.

21. The sensor as recited in claim 12, further comprising a hygroscopic and/or hydrophilic coating adhered to said distal end.

22. The sensor as recited in claim 12, further comprising an electrical and display means which is in communication with the sensor and processes information obtained from said sensor for presenting a pH reading.

23. A controlled activation sensor kit for monitoring pH or other constituents:

a non-activated sensor, said non-activated sensor comprising;

an outer tubular member and an inner tubular member, enclosing one or more inner tubular members, said outer tubular member having a terminal end;

a dry state wick material located within said inner tubular member, said wick material impregnated with a dry matrix of hydroscopic and/or hydrophilic materials, said wick material including one or more micro-channels, said dry state wick material acting as a capillary tube that facilitates liquid flow;

a dry state reference electrode, said dry state reference electrode comprising a silver wire terminally coated with silver chloride coating, said dry state reference electrode enclosed in a proximal position with said dry state wick material within a first area;

an expansion plug located proximal to said dry state wick and within said inner tubular member, said expansion plug designed to regulate the amount of liquid absorbed and control the electrolyte concentration;

one or more sodium chloride rods that are positioned in close proximity to the reference wick;

an antimony metal segment enclosed within a second area, said outer tubular member electrically isolates said antimony metal segment from said reference electrode;

a hydration solution stored in a container.