Free Standing Metal-Ion Doped Thin Films

A method for depositing a film on a hydrophobic silicone substrate, the method comprising:

• (a) depositing a first deposition solution comprising at least one positively charged polymer, wherein the pH of the solution is at or above the pKa of the at least one positively charged polymer and wherein the first exposure occurs for about 8 seconds to about 30 seconds to form a first layer of said first deposition material;
• (b) applying a rinse solution to remove any excess unbound polymer from the first deposition solution, allowing it to reside on the surface for a period of time trinse, of about 8-90 seconds;
• (c) removing excess rinse solution using a diffusion barrier removal step whereby a layer of rinse solution of 2-5 microns is left on the polymer layer;
• (d) depositing a second deposition solution comprising at least one negatively charged polymer, wherein the pH of the solution is at or above the pKa of the at least one negatively charged polymer, the solution contains a counterion for the at least one negatively charged polymer, wherein the counterion is provided by one or more of calcium nitrate, aluminum nitrate, copper chloride, magnesium chloride, manganese chloride, sodium chloride, calcium chloride, potassium chloride, copper sulfate, magnesium sulfate, sodium acetate, calcium acetate, sodium carbonate, potassium carbonate, calcium carbonate, or manganese carbonate, and wherein the second exposure occurs for about 8 seconds to about 30 seconds to form a second layer of said second deposition material;
• (e) applying a rinse solution to remove any excess unbound polymer from the second deposition solution, allowing it to reside on the surface for a period of time trinse of about 8-90 seconds;
• (f) removing excess rinse solution using a diffusion barrier removal step whereby a layer of rinse solution of 2-5 microns is left on a second layer made from the second deposition material;
• (g) exposing the film to a metal ion solution for a period of about 45 seconds to 3 minutes, whereby the counterion is exchanged for a metal ion from the metal ion solution;
• (h) applying a first rinse solution to remove any unbound excess metal ions for a period of time trinse equal to about 45 seconds to about 3 minutes;
• (i) applying a reducing solution to the film for a period of about 45 sec to 3 minutes;
• (j) applying a second rinse solution for a period of time trinse equal to about 45 seconds to about 3 minutes;
• (k) depositing a third deposition solution comprising a hydrophilic polymer and an additive to form a layer of the hydrophilic polymer with the additive less than 5 mil (125 micron) thick after drying, wherein the additive is a hyaluronic acid, an analgesic, a surfactant, a metal ion salt;
• and
• (l) drying to form a completed film.