Thin film polymer structure having different modification on opposite sides thereof

1. A method for preparing a thin film polymer structure,

wherein the thin film polymer structure prepared by the method has two faces, one face being each of the opposite sides of the thin film polymer structure, and has a different functional substance bound to each of the two faces, said thin film polymer structure being obtained by the steps of:

(a) adsorbing polyfunctional molecules to an arbitrarily shaped soluble region of a substrate body in an interface between the substrate body and a liquid phase, wherein the polyfunctional molecules are at least one polyfunctional macromer selected from the group consisting of polylactic acid, polylactic acid/glycolic acid copolymer, and polycaprolactone, provided that said polyfunctional macromer is not a polymer bead;

(b) crosslinking the adsorbing polyfunctional molecules by thermally crosslinking the polyfunctional molecules at 60-120° C. to form a polymer thin film having two faces, an exposed face referred to as an A surface and a reverse face on the opposite side of the thin film facing the substrate body, the reverse face referred to as a B surface;

(c) bonding a functional substance to the A surface of the formed polymer thin film;

(d) exfoliating the polymer thin film from the substrate body by dissolving the soluble region of the substrate body with a solvent;

(e) applying the A surface inclusive of the bonded functional substance of the exfoliated polymer thin film directly atop a soluble support film formed on a substrate body other than the substrate body in step (a) the soluble support film being formed by application of an aqueous solution comprising a soluble support film polymer to the substrate body other than the substrate body in step (a), wherein said A surface inclusive of the bonded functional substance of the exfoliated polymer thin film bonds to the soluble support film solely by secondary bonding forces between the A surface inclusive of the bonded functional substance of the exfoliated polymer thin film and the soluble support film;

(f) bonding to the B surface of the polymer thin film a functional substance different from the functional substance in step (c); and

(g) dissolving the soluble support film with a solvent to release a thin film polymer structure having a different functional substance on the A surface and the B surface of the thin film polymer structure,

wherein each of the soluble support film and soluble region is independently formed of polyethylene glycol, polyacrylamide, polyvinyl alcohol, or polysaccharide, said polysaccharide excluding cellulose acetate.

2. The method according to claim 1 , wherein the functional substance is at least one of the following selected from the group consisting of a polymer compound, a polyelectrolyte, a protein, a peptide, a polysaccharide and a biotin derivative.

3. The method according to claim 2 , wherein the polymer compound comprises poly(ethyleneglycol).

4. The method according to claim 1 , wherein the substrate bodies are entirely or partially formed of at least one of the following selected from the group consisting of a metal or an oxide cover layer thereof, silicon, silicon rubber, silica, glass, mica, graphite, an organic polymer, and apatite.

5. The method according to claim 1 , wherein the solvent in steps (d) and (g) is selected from acetone, ethyl acetate, an alcohol, water, or an aqueous solution and will not dissolve the thin film polymer structure.

6. The method according to claim 1 , wherein the A surface of the exfoliated polymer thin film bonds to the soluble support film by a secondary bonding force selected from the group consisting of electrostatic interaction, hydrogen bonding or Van der Waals' force.

7. A method for preparing a thin film polymer structure,

wherein the thin film polymer structure prepared by the method has two faces, one face being each of the opposite sides of the thin film polymer structure, and has a different functional substance bound to each of the two faces, said thin film polymer structure being obtained by the steps of:

(a) adsorbing polyfunctional molecules to an arbitrarily shaped soluble region of a substrate body in an interface between the substrate body and a liquid phase, wherein the polyfunctional molecules are at least one polyfunctional macromer selected from the group consisting of polylactic acid, polylactic acid/glycolic acid copolymer, and polycaprolactone, provided that said polyfunctional macromer is not a polymer bead;

(b) crosslinking the adsorbing polyfunctional molecules by thermally crosslinking the polyfunctional molecules at 60-120° C. to form a polymer thin film having two faces, an exposed face referred to as an A surface and a reverse face on the opposite side of the thin film facing the substrate body, the reverse face referred to as a B surface;

(c) bonding a functional substance to the A surface of the formed polymer thin film;

(d) exfoliating the polymer thin film from the substrate body by dissolving the soluble region of the substrate body with a first solvent;

(e) applying the A surface inclusive of the bonded functional substance of the exfoliated polymer thin film directly atop a soluble support film formed on a substrate body other than the substrate body in step (a), wherein said A surface inclusive of the bonded functional substance of the exfoliated polymer thin film bonds to the soluble support film solely by secondary bonding forces between the A surface inclusive of the bonded functional substance of the exfoliated polymer thin film and the soluble support film;

(f) bonding to the B surface of the polymer thin film a functional substance different from the functional substance in step (c); and

(g) dissolving the soluble support film with a solution consisting essentially of a second solvent selected from the group consisting of acetone, ethyl acetate, an alcohol, water, and a mixture thereof to release a thin film polymer structure having a different functional substance on the A surface and the B surface of the thin film polymer structure,

wherein each of the soluble support film and soluble region is independently formed of polyethylene glycol, polyacrylamide, polyvinyl alcohol, or polysaccharide, said polysaccharide excluding cellulose acetate.

8. The method according to claim 7 , wherein the second solvent is water.