Biocidal fibrous and film materials comprising silver and chlorite ions

• US 8,900,610 B2
• Filed: 08/30/2005
• Issued: 12/02/2014
• Est. Priority Date: 08/30/2004
• Status: Active Grant

• Current Assignee: Southwest Research Institute
• Original Assignee: Southwest Research Institute
• Inventors: Wellinghoff, Stephen T.
• Primary Examiner(s): Pak, John
• Assistant Examiner(s): Schlientz, Nathan W
• Application Number:
  US11/215,738
• Publication Number:
  US 20070237810A1
• Time in Patent Office: 3,381 Days
• Field of Search: 424/405, 424/445, 424/447, 424/618, 424/661, 514/772.1, 514/772.5, 514/772.6
• US Class Current: 424/405
• CPC Class Codes: A01N 2300/00 Combinations or mixtures of active ingredients covered by classes A01N27/00 - A01N65/48 with other active or formulation relevant ingredients, e.g. specific carrier materials or surfactants, covered by classes A01N25/00 - A01N65/48
• CPC Class Codes: A01N 25/10 Macromolecular compounds
• CPC Class Codes: A01N 59/00 Biocides, pest repellants or attractants, or plant growth regulators containing elements or inorganic compounds
• CPC Class Codes: A01N 59/16 Heavy metals; Compounds thereof
• CPC Class Codes: A61K 33/38 Silver; Compounds thereof
• CPC Class Codes: A61K 47/6955 the form being a plaster, a bandage, a dressing or a patch
• CPC Class Codes: A61L 15/46 Deodorants or malodour counteractants, e.g. to inhibit the formation of ammonia or bacteria
• CPC Class Codes: A61L 2300/104 Silver, e.g. silver sulfadiazine
• CPC Class Codes: A61L 2300/106 Halogens or compounds thereof, e.g. iodine, chlorite
• CPC Class Codes: A61L 2300/404 Biocides, antimicrobial agents, antiseptic agents
• CPC Class Codes: A61L 2300/602 Type of release, e.g. controlled, sustained, slow

Abstract

Disclosed are compositions comprising a hydrophilic polymer, a hydrophobic polymer, a silver ion, and a chlorite anion, wherein the silver ion associates with at least one hydrophilic or hydrophobic polymer, and wherein the chlorite ion associates with the hydrophilic polymer. Also disclosed are methods of making a photo-stable silver ion and chlorite ion containing wound dressing and methods of reducing or preventing infection of a wound by using the compositions and wound dressings of the present invention.

Claims

1. A composition comprising:

(a) a hydrophilic polymer comprising a polyvinylpyridine hydrophilic polymer and a chlorite anion;

(b) a hydrophobic polymer comprising carboxylate substituted hydrophobic polymer; and

(c) a silver ion present at a level of 0.01% to 9.9% by weight,

wherein the silver ion is associated with a pyridine group of said polyvinylpyridine hydrophilic polymer and a negatively charged carboyxlate group of said carboxylate substituted hydrophobic polymer so as to form a molecular bridge between the hydrophilic polymer and the hydrophobic polymer; and

wherein said chlorite anion oxidizes any silver metal formed from said silver ion to inhibit formation of silver metal clusters.

2. The composition of claim 1, wherein the association between the silver ion and the hydrophilic polymer or the hydrophobic polymer is characterized as an ionic bond, a covalent bond, or a co-ordinate bond.

3. The composition of claim 1, wherein the chlorite anion is associated with the hydrophilic polymer by an electrostatic interaction.

4. The composition of claim 1, wherein the chlorite anion is associated with a cation.

5. The composition of claim 1, wherein a cation, associated with said anion, is selected from the group consisting of Na⁺, K⁺, Li⁺, Cs⁺, Rb⁺, a tetra-alkylammonium cation, and mixtures thereof.

6. The composition of claim 1, wherein the hydrophobic or hydrophilic polymer comprises an anionic group.

7. The composition of claim 6, wherein the anionic group is a —

COO⁻

group.

8. The composition of claim 1, wherein the hydrophilic or hydrophobic polymers are substituted with a quaternary nitrogen azaaromatic or aliphatic group, wherein the quaternary nitrogen in the azaaromatic or aliphatic group comprises an anion.

9. The composition of claim 8, wherein the anion is Cl⁻

.

10. The composition of claim 1, wherein the silver ion is obtained from AgBF₄, AgPF₆, AgSO₃CF₃, AgClO₄, AgNO₃, n-alkylArSO₂Ag, or n-alkylCOOAg.

11. The composition of claim 1, wherein the composition comprises between about 1% to about 10% by weight of chlorite ion.

12. The composition of claim 1, wherein the composition comprises between about 20% to about 80% by weight of hydrophilic polymer.

13. The composition of claim 1, wherein the compositions comprises between about 20% to about 80% by weight of a hydrophobic polymer.

14. The composition of claim 1, wherein the hydrophilic/hydrophobic polymer ratio is between 1/4 to about 4/1.

15. The composition of claim 1, wherein the composition is transparent.

16. The composition of claim 1, wherein the composition is a controlled release silver ion composition.

17. The composition of claim 1, wherein the composition is comprised on the surface of a medical device.

18. The composition of claim 17, wherein the medical device is selected from the group consisting of a scalpel, a tong, a retractor, and a glove.

19. The composition of claim 1, wherein the composition is comprised in a wound dressing.

20. The composition of claim 1, wherein the composition is a wound dressing.

21. The composition of claim 1, wherein the hydrophobic polymer is selected from the group consisting of alkyl acrylates, polymethylmethacrylate, polybenzylmethacrylate, polyphenylmethacrylate, and polyvinyl cinnamate;

said polymer comprising partially neutralized carboxylic groups selected from the group consisting of acrylic acid monomer, methacrylic acid monomer, maleic acid, hydrolyzed anhydride monomer, substituted phthalic acid, hydrolyzed acid anhydride monomer, and hydrolyzed α

-hydroxyacid ester so as to provide both acidic carboxylic groups and carboxylate anions.

22. The composition of claim 1, wherein the silver ion is photo-stable or thermo-stable.

23. The composition of claim 1, wherein the silver ion associates with said pyridine group of said polyvinylpyridine hydrophilic polymer through a metal co-ordination bond.

24. The composition of claim 1, wherein the silver ion bonds to an arene group of a styrene-acrylic acid copolymer through a d-π

interaction.

25. The composition of claim 1, wherein said chlorite anion stabilizes the silver ion.

26. The composition of claim 1, wherein said chlorite anion minimizes coloring due to silver metal particles in the visible region spectrum.

27. The composition of claim 1, wherein said chlorite anion maximizes the availability of silver ion to act as a biocide.