Compositions For Wound Treatment

Abstract

A wound dressing composition comprising a chitosan and an oxidized cellulose. For example, the composition may be in the form of a sponge formed by freeze drying an aqueous dispersion of chitosan and oxidized regenerated cellulose (ORC). The composition is especially suitable for the treatment of chronic wounds.

1 . A wound dressing composition comprising a chitosan and an oxidized cellulose. 
     
     
         2 . The wound dressing composition of  claim 1 , wherein the chitosan and the oxidized cellulose are intimately mixed in the wound dressing composition. 
     
     
         3 . The wound dressing composition of  claim 1 , wherein the oxidized cellulose is in the form of dispersed fibers or powder. 
     
     
         4 . The wound dressing composition of  claim 1 , wherein the oxidized cellulose and the chitosan are dispersed in a semi-solid or solid vehicle for topical application. 
     
     
         5 . The wound dressing composition of  claim 1 , wherein the oxidized cellulose comprises oxidized regenerated cellulose (ORC). 
     
     
         6 . The wound dressing composition of  claim 1 , wherein the oxidized cellulose and the chitosan together make up at least 25% by weight of the wound dressing composition on a dry weight basis. 
     
     
         7 . The wound dressing composition of  claim 6 , wherein the oxidized cellulose and the chitosan together make up at least 50% by weight of the wound dressing composition on a dry weight basis. 
     
     
         8 . The wound dressing composition of  claim 1 , wherein the wound dressing composition further comprises from about 0.01 to about 5% by weight on a dry weight basis of one or more wound healing therapeutic substances. 
     
     
         9 . The wound dressing composition of  claim 1 , wherein the wound dressing composition is a flexible film. 
     
     
         10 . The wound dressing composition of  claim 1 , wherein the chitosan and the oxidized cellulose are present in a weight ratio of chitosan to oxidized cellulose from 1:10 to 10:1. 
     
     
         11 . The wound dressing composition of  claim 10 , wherein the weight ratio of chitosan to oxidized cellulose is in the range 1:4 to 4:1. 
     
     
         12 . A wound dressing comprising the wound dressing composition of  claim 1 . 
     
     
         13 . The wound dressing of  claim 12 , wherein the wound dressing is sterile and packaged in a microorganism-impermeable container. 
     
     
         14 . A method of providing therapy to a wound, the method comprising applying the wound dressing composition of  claim 1 . 
     
     
         15 . The method of  claim 14 , wherein the wound is a chronic wound. 
     
     
         16 . The method of  claim 15 , wherein the chronic wound is selected from the group consisting of venous ulcers, decubitis ulcers and diabetic ulcers. 
     
     
         17 . A method of separating cell growth factors from a biological sample or organism, the method comprising:
 contacting the biological sample or organism with the wound dressing composition of  claim 1  to bind the growth factors to the wound dressing composition, wherein the contacting the wound dressing composition is carried out in vivo or in vitro; and,   removing the wound dressing composition from the sample or organism.   
     
     
         18 . A method according to  claim 17 , further comprising recovering the bound growth factors from the wound dressing composition after removing the wound dressing composition from the sample or organism. 
     
     
         19 . A method of preparing an active wound dressing material comprising the steps of:
 contacting the wound dressing composition according to  claim 1  with a biological medium containing cell growth factors to bind the cell growth factors to the material; and   (ii) washing and drying the wound dressing material having the cell growth factors bound thereto to form the active wound dressing material.   
     
     
         20 . A method according to  claim 19 , wherein the cell growth factors comprise platelet derived growth factor.