Antioxidant and antimicrobial wound dressing materials

Abstract

A wound dressing material may include a polymeric substrate, a silver salt, and a dyestuff to photostabilize the silver salt. The substrate may include collagen and/or oxidized regenerated cellulose complexed to Ag+, and the dyestuff may, for example, be an aniline or acridine dye. Also disclosed are methods of making such materials, and wound dressings that include such materials.

1 . A wound dressing material comprising a polymeric substrate, a silver salt, and a dyestuff to photostabilize the silver salt. 
     
     
         2 . A wound dressing material according to  claim 1 , wherein the substrate comprises a solid bioabsorbable material, preferably selected from the group consisting of collagens, oxidized celluloses, chitosans, galactomannans, glycosaminoglycans, and mixtures thereof. 
     
     
         3 . A wound dressing material according to  claim 2 , wherein the substrate comprises a solid bioabsorbable material selected from the group consisting of collagens, oxidized celluloses, chitosans, and mixtures thereof. 
     
     
         4 . A wound dressing material according to  claim 1 , wherein the substrate is selected from the group consisting of celluloses, alginates, polyacrylates, polyurethanes, polyamides, and mixtures thereof. 
     
     
         5 . A wound dressing material according to  claim 1 , wherein the wound dressing material is in the form of a continuous solid sheet, an apertured solid sheet, a web, a woven fabric, a knitted fabric, a nonwoven fabric, a freeze-dried sponge or a solvent-dried sponge. 
     
     
         6 . A wound dressing material according to  claim 1 , wherein the polymeric substrate comprises an anionic polymer, and said silver salt comprises a salt of Ag +  with the anionic polymer. 
     
     
         7 . A wound dressing material according to  claim 1 , wherein the composition comprises from about 0.01 wt. % to about 5 wt. % of silver, based on the dry weight of the composition. 
     
     
         8 . A wound dressing material according to  claim 1 , wherein the dyestuff comprises an antioxidant dyestuff, for example selected from the group consisting of aniline dyes, acridine dyes, thionine dyes, bis-naphthalene dyes, thiazine dyes, azo dyes, anthraquinones, and mixtures thereof. 
     
     
         9 . A wound dressing material according to  claim 8 , wherein the antioxidant dyestuff is selected from the group consisting of gentian violet, aniline blue, methylene blue, crystal violet, acriflavine, 9-aminoacridine, acridine yellow, acridine orange, proflavin, quinacrine, brilliant green, trypan blue, trypan red, malachite green, azacrine, methyl violet, methyl orange, methyl yellow, ethyl violet, acid orange, acid yellow, acid blue, acid red, thioflavin, alphazurine, indigo blue, methylene green, and mixtures thereof. 
     
     
         10 . A wound dressing material according to  claim 1 , wherein the dyestuff is present in an amount of from about 0.2 to about 2 wt. % based on the dry weight of the material. 
     
     
         11 . A wound dressing material according to  claim 1 , wherein the polymeric substrate consists essentially of a mixture of an oxidized cellulose with a collagen and/or a chitosan. 
     
     
         12 . A wound dressing material according to  claim 1 , wherein the material is sterile and packaged in a microorganism-impermeable container. 
     
     
         13 . A wound dressing material according to  claim 1 , wherein the material has a free radical activity in the diphenylpicrylhydrazyl (DPPH) test for antioxidant activity as herein defined of at least about 15%. 
     
     
         14 . A method for treating a wound, the method comprising administering to the wound a wound dressing material of  claim 1 . 
     
     
         15 . The method of  claim 14 , wherein the wound is a chronic wound, preferably selected from the group consisting of ulcers of venous ulcers, decubitus ulcers, or diabetic ulcers. 
     
     
         16 - 19 . (canceled)