Biological tissue for surgical implantation

Abstract

A method of treating a biological tissue that enables dry storage of said tissue is disclosed. In one embodiment, the method comprises contacting the biological tissue with a non-aqueous treatment solution comprising a polyhydric alcohol and a C 1 -C 3 alcohol and removing a portion of the treatment solution from the solution-treated biological tissue. Also disclosed is biological tissue prepared using the above process and prosthetic devices made with such tissue.

What is claimed is: 
     
         1 . A method of treating a fixed pericardial tissue, the method comprising:
 placing the fixed pericardial tissue in an immersion bath comprising a treatment solution comprising 70% to 95% by volume of one or more polyhydric alcohols and 5% to 30% by volume of an alcohol, wherein the one or more polyhydric alcohols are selected from the group consisting of: glycerol, ethylene glycol, polyethylene glycol, propylene glycol, and butylene glycol; and   exposing the fixed pericardial tissue to ambient air or an inert environment to substantially dry the fixed pericardial tissue.   
     
     
         2 . The method of  claim 1 , wherein the treatment solution comprises two or more polyhydric alcohols. 
     
     
         3 . The method of  claim 2 , wherein the treatment solution comprises glycerol and polypropylene glycol. 
     
     
         4 . The method of  claim 1 , wherein the alcohol is one or more of a C 1 -C 3  alcohol. 
     
     
         5 . The method of  claim 4 , wherein the one or more C 1 -C 3  alcohols are selected from the group consisting of: methanol, ethanol, isopropanol, and n-propanol. 
     
     
         6 . The method of  claim 5 , wherein the one or more C 1 -C 3  alcohols is ethanol. 
     
     
         7 . The method of  claim 1 , further comprising placing the fixed pericardial tissue in a second immersion bath before the exposing;
 wherein the second immersion bath comprises a second treatment solution comprising 70% to 95% by volume of one or more polyhydric alcohols and 5% to 30% by volume of an alcohol; and   wherein the one or more polyhydric alcohols are selected from the group consisting of: glycerol, ethylene glycol, polyethylene glycol, propylene glycol, and butylene glycol.   
     
     
         8 . The method of  claim 7 , wherein the treatment solution and the second treatment solution are the same. 
     
     
         9 . The method of  claim 7 , wherein the treatment solution and the second treatment solution are different. 
     
     
         10 . The method of  claim 1 , wherein the exposing is performed in a clean room or in a laminar flow bench. 
     
     
         11 . The method of  claim 10 , wherein the exposing is performed at a temperature of about 15° C. to about 25° C. and at a relative humidity of less than about 50%. 
     
     
         12 . The method of  claim 1 , wherein:
 the exposing is performed in an inert environment; and   the inert environment is under nitrogen.   
     
     
         13 . The method of  claim 1 , further comprising packaging the fixed pericardial tissue in a container or package essentially free of liquid to provide a packaged fixed pericardial tissue. 
     
     
         14 . The method of  claim 13 , further comprising sterilizing the packaged fixed pericardial tissue by exposure to ionizing radiation or sterilizing gas. 
     
     
         15 . The method of  claim 14 , wherein:
 the sterilizing is performed with sterilizing gas; and   the sterilizing gas is ethylene oxide.   
     
     
         16 . The method of  claim 15 , wherein the sterilizing comprises exposing the packaged fixed pericardial tissue to 10% ethylene oxide and 90% hydrochlorofluorocarbon at a chamber pressure of 8 to 10 psig at a temperature of about 38° C. for about 24 hours or at a temperature of 54° C. to 57° C. for about 130 minutes.