A flexible free-standing ultrathin or thin protein membrane and its fabrication method

摘要

[Purpose] A purpose of this invention is to provide a robust and flexible free-standing ultrathin(nano) or thin pure protein membrane which enables a rapid and simple separation(or condensation) of relatively small(M.W.=ca.1,000 Da) molecules. [Summary] A flexible free-standing ultrathin(nano) or thin protein membrane can be fabricated by a method comprising following steps: (1) A dilute metal(Cd, Cu or Zn) nitrate or chloride solution is kept under neutral or weak basic pH to spontaneously form metal(Cd, Cu or Zn) hydroxide nanostrands,
(2) The above metal(Cd, Cu or Zn) hydroxide nanostrands and protein solution are mixed to obtain composite nanofibers made of protein and the said metal hydroxide nanostrands;
(3) The obtained dispersion of composite nanofibers is filtered on a filter.
(4) Proteins contained in the composite are cross-linked by bifunctional cross-linkers; and
(5) Metal(Cd, Cu or Zn) hydroxide nanostrands are removed from them.