Two-dimensional aggregation and fixation of protein by injection into a

Abstract

Protein is two-dimensionally aggregated and fixed to produce a functional thin film. A denatured film of a first protein is formed on the surface of a substrate solution such as an aqueous sugar or salt solution. A solution of a second protein which may be the same as or different from the first protein is then injected below the surface of the substrate solution at a distance sufficient not to disturb the surface. The substrate solution has a higher surface tension and specific gravity than the second protein solution causing the second protein to float between the denatured protein film and the substrate solution surface to form the two-dimensionally aggregated and fixed protein. The denatured film of first protein may be formed by injection of a solution of the first protein below the surface of the substrate solution. The aggregated and fixed protein can be heated and then transferred onto a solid surface such as in the formation of a biosensor. A three-dimensional multilayer laminate of the two-dimensional aggregate may also be formed. In an alternative embodiment, a lipid monolayer is formed on the surface of the substrate solution, a protein solution is injected below the surface of the substrate solution and the protein floats between the substrate solution surface and the lipid monolayer to form the two-dimensionally aggregated and fixed protein.