Chitosan-based hemostatic textile

Abstract

A microfibrillar high molecular weight chitosan-based textile can be used as a hemostat. The chitosan has been treated in a nitrogen field by applying energy to ionize nitrogen in and around the chitosan textile. A single or multiple such treatments may be employed. For example, the chitosan textile may be irradiated under nitrogen using γ-irradiation, treated under a nitrogen plasma, or both.

What is claimed is: 
     
         1 . A method of making a hemostatic textile material, comprising processing crab shells to obtain a high molecular weight chitosan having a molecular weight in a range about 600-800 kDa and a degree of deacetylation of about 75-88%, processing the high molecular weight chitosan into a textile comprising a network of chitosan fibers, and irradiating the high molecular weight chitosan textile under nitrogen using γ-irradiation. 
     
     
         2 . The method of  claim 1  additionally comprising treating the chitosan textile under a nitrogen plasma. 
     
     
         3 . The method of  claim 2  additionally comprising soaking the chitosan fibers in an alcohol prior to treating with γ-irradiation or plasma. 
     
     
         4 . The method of  claim 1  additionally comprising packaging the fibrous high molecular weight chitosan textile in a nitrogen field and sealing the package so that the chitosan textile is sealed within a nitrogen environment prior to γ-irradiation, and wherein the chitosan textile remains sealed within the package during irradiation. 
     
     
         5 . The method of  claim 4  additionally comprising treating the chitosan textile under a nitrogen plasma, wherein the chitosan textile remains sealed within the package during nitrogen plasma treatment. 
     
     
         6 . The method of  claim 5  comprising packaging the chitosan textile in a dry condition. 
     
     
         7 . The method of  claim 4 , wherein the packaging comprises metalized packaging. 
     
     
         8 . The method of  claim 4  additionally comprising forming the hemostatic chitosan textile into a woven or nonwoven fabric prior to packaging the chitosan. 
     
     
         9 . The method of  claim 4  additionally comprising treating the chitosan fibers with an acetic acid solution. 
     
     
         10 . The method of  claim 9 , wherein the acetic acid is a glacial acetic acid so as to form an ammonium salt of chitosan. 
     
     
         11 . A method of making a textile hemostatic material, comprising providing a high molecular weight chitosan having a molecular weight of about 600-800 kDa and a degree of deacetylation chosen to facilitate formation of dry fibers, processing the high molecular weight chitosan into a fibrous textile, and treating the high molecular weight chitosan textile under a nitrogen plasma. 
     
     
         12 . The method of  claim 11 , wherein the step of sterilizing the fibrous chitosan under nitrogen is configured to increase the concentration of amino groups on the chitosan fibers. 
     
     
         13 . The method of  claim 11 , comprising treating the chitosan textile in a nitrogen plasma at ambient temperature 
     
     
         14 . The method of  claim 11 , wherein the chitosan has a degree of deacetylation of about 75-88%. 
     
     
         15 . The method of  claim 14 , wherein the chitosan has a degree of deacetylation of about 80-85%. 
     
     
         16 . The method of  claim 14 , wherein the chitosan has a degree of deacetylation of about 85%.