Flexible free-standing ultrathin or thin protein membrane

Abstract

A flexible porous free-standing protein membrane includes cross-linked protein. At least part of pores of the porous membrane is formed by removing nanostrands whose diameters are 2-3 nm, the cross-linked protein is cross-linked by a bifunctional cross-linker, and a thickness of the protein membrane is 10 μm or less.

What we claim is: 
     
         1 . A flexible porous free-standing protein membrane, comprising:
 cross-linked protein,   wherein at least part of pores of said porous membrane is formed by removing nanostrands whose diameters are 2-3 nm,   the cross-linked protein is cross-linked by a bifunctional cross-linker, and   a thickness of the protein membrane is 10 μm or less.   
     
     
         2 . A composite protein membrane formed by integrating a protein membrane and another molecular membrane,
 wherein said protein membrane is a free-standing protein membrane according to  claim 1 , and   a thickness of the protein membrane is 10 μm or less.   
     
     
         3 . The composite protein membrane according to  claim 2 , wherein said molecular membrane and said protein membrane are cross-linked by a bifunctional cross-linker for integration. 
     
     
         4 . The composite protein membrane according to  claim 2 , wherein said molecular membrane is formed by dendrimers having terminal NH 2  groups.