Method for silk fibroin gelation using sonication

Abstract

This invention provides for a process of rapidly forming silk fibroin gelation through ultrasonication. Under the appropriate conditions, gelation can be controlled to occur within two hours after the ultrasonication treatment. Biological materials, including viable cells, or therapeutic agents can be encapsulated in the hydrogels formed from the process and be used as delivery vehicles.

What is claimed is: 
     
         1 . A process of rapidly forming silk fibroin gelation, comprising exposing silk fibroin to a treatment comprising ultrasonication for a period of about 5 seconds to about 60 seconds to initiate gelation, wherein substantial silk fibroin gelation forms less than 24 hours after the ultrasonication treatment. 
     
     
         2 . The process of  claim 1 , wherein the silk fibroin gelation forms less than two hours after the ultrasonication treatment. 
     
     
         3 . The process of  claim 1 , wherein the silk fibroin undergoes gelation at a time period ranging from about five minutes to about two hours after the ultrasonication treatment. 
     
     
         4 . The process of  claim 1 , wherein the treatment further comprises a salt solution. 
     
     
         5 . The process of  claim 4 , wherein the salt solution comprises ions selected from the group consisting of potassium, calcium, sodium, magnesium, copper, zinc, and combinations thereof. 
     
     
         6 . The process of  claim 5 , wherein the salt is potassium, the salt concentration is less than 100 mM, and the pH of the salt concentration is about pH 4 or lower. 
     
     
         7 . The process of  claim 1 , wherein the silk fibroin is in the form of an aqueous solution having a pH that is about pH 4 or lower or is about pH 7.5 or higher.