Tissue allograft sterilization method

Abstract

The invention is a novel method of sterilizing bone and soft tissues intended for human transplantation. In one embodiment the process includes steps of subjecting transplants to high hydrostatic pressures of aqueous fluid to which chlorhexidine gluconate or similar sterilizing chemicals have been added.

What is claimed: 
     
         1 . A sterilized bone graft suitable for transplantation into a human from cadaver bone produced by the process, the process comprising the steps of:
 (a) initially washing the cadaver bone;   (b) exposing the washed cadaver bone to a jet stream from a water jet system, which has been adjusted below a cutting capacity of the water jet system, to form a jet stream-washed bone graft;   (c) delivery of one or more sterilizing solutions containing chlorhexidine gluconate, Dakin solution, chloramineT and/or other solutions generating hypochlorous acid to the jet stream-washed bone graft using a high pressure chamber having a high hydrostatic pressure so as to achieve microbial inactivation of the bone graft;   (d) re-washing the microbial inactivated bone graft under high hydrostatic pressure in the range of 100-600 MPa to remove residuals of the one or more sterilizing solutions; and   (e) immersing the re-washed bone graft in Dakin solution or other solution producing hypochlorous acid at normal atmospheric pressure.   
     
     
         2 . The bone graft produced by the process of  claim 1  wherein the process further comprises:
 treating of such grafts with chlorhexidine gluconate under high hydrostatic pressure. 
 
     
     
         3 . The bone graft produced by the process of  claim 1  wherein the process further comprises:
 grafts are treated with 0.5 to 5% chlorhexidine gluconate. 
 
     
     
         4 . The bone graft produced by the process of  claim 1  wherein the process further comprises:
 the graft is essentially free from bacterial, fungal, viral or parasitic contamination. 
 
     
     
         5 . The bone graft produced by the process of  claim 1  wherein the process further comprises:
 application of Dakin solution and/or other compounds which produce hypochlorous acid under high hydrostatic pressure. 
 
     
     
         6 . The bone graft produced by the process of  claim 1  wherein the process further comprises:
 treatment of bone, cartilage and soft tissue grafts suitable for implantation into a human with Dakin solution or other solutions producing hypochlorous acid at normal atmospheric pressure. 
 
     
     
         7 . The bone graft produced by the process of  claim 1  wherein the process further comprises:
 washing of said washed and sterilized grafts with distilled water. 
 
     
     
         8 . The bone graft produced by the process of  claim 1  wherein the process further comprises:
 washing with sterile saline. 
 
     
     
         9 . The bone graft produced by the process of  claim 1  wherein the process further comprises:
 producing prewashed bone, cartilage and soft tissue graft with sterile water or sterile physiologic saline with velocity high pressure stream. 
 
     
     
         8 . The bone graft produced by the process of  claim 1  wherein the process further comprises:
 cutting prewashed bone, cartilage or soft tissue suitable for transplantation into a human with a “Jet Set” or other high velocity high pressure, focused water jet stream. 
 
     
     
         9 . The bone graft produced by the process of  claim 1  wherein the process further comprises:
 washing bone, cartilage and soft tissue graft in solutions oxygenated under pressure or carbonated under high pressure. 
 
     
     
         10 . A method of producing bone, cartilage or soft tissue grafts suitable for transplantation into a human comprising; washing said grafts under high pressure to produce a cleaned graft; treating said graft with one or two decontaminating solutions under high hydrostatic pressure; washing said grafts with water or saline solutions oxygenated under high hydrostatic pressure; washing said grafts with water or saline solutions carbonated under high hydrostatic pressure. 
     
     
         11 . The method of  claim 10  wherein such washing and sterilizing treatments comprise one or more soaking, treatment at high pressure with sterilizing solutions and washing in solutions producing effervescence.