Polyelectrolyte multilayer films at liquid-liquid interfaces and methods for providing and using same
The present invention is directed to methods for providing a polyelectrolyte multilayer film at a liquid-liquid interface. Such methods include steps of sequentially-depositing layers of cationic and anionic polyelectrolytes at a liquid-liquid interface that is formed between immiscible first and second liquids whereby a polyelectrolyte multilayer film is provided at the liquid-liquid interface. In certain preferred embodiments, the first liquid is an aqueous solution and the second liquid is a liquid crystal. In alternative embodiments, the first liquid is an aqueous solution and the second liquid is an oil. The invention further encompasses polyelectrolyte multilayer films provided by the disclosed methods as well as applications utilizing such materials.
1. A method for providing a polyelectrolyte multilayer film at a liquid-liquid interface, comprising steps of sequentially-depositing layers of anionic and cationic polyelectrolytes at a liquid-liquid interface that is formed between immiscible first and second liquids, wherein the first liquid is an aqueous solution and the second liquid is a liquid crystal, whereby a polyelectrolyte multilayer film is provided at said liquid-liquid interface.
2. The method according to claim 1 wherein the liquid crystal is in the form of a droplet.
3. The method according to claim 1 wherein the second liquid is in the form of a droplet.
4. A method for providing a polyelectrolyte multilayer film at an aqueous-liquid crystal interface, comprising steps of sequentially-depositing layers of cationic and anionic polyelectrolytes at an aqueous-liquid crystal interface that is formed between an aqueous phase and a liquid crystal phase whereby a polyelectrolyte multilayer film is provided at said aqueous-liquid crystal interface.
5. The method according to claim 4 wherein the polyelectrolyte multilayer film is capable of interacting with an analyte present in the aqueous solution thereby causing a change in orientation or ordering of the liquid crystal.
6. The method according to claim 4 wherein the polyelectrolyte multilayer film includes an excipient capable of interacting with an analyte present in the aqueous solution thereby causing a change in orientation or ordering of the liquid crystal.
7. The method according to claim 6 wherein said excipient is a ligand or a receptor capable of selectively-binding said analyte, an enzyme capable of catalyzing a transformation of the analyte, a molecule capable of undergoing a chemical reaction in the presence of the analyte, or an enzyme substrate capable of being transformed by said analyte.
8. The method according to claim 4 wherein the polyelectrolyte multilayer film is deposited directly on the liquid crystal phase.
9. A method for providing an unsupported polyelectrolyte multilayer film comprising steps of:
(a) providing a liquid-liquid interface between immiscible first and second liquids, wherein the first liquid is an aqueous solution and the second liquid is a liquid crystal;
(b) sequentially-depositing layers of cationic and anionic polyelectrolytes at the liquid-liquid interface whereby a polyelectrolyte multilayer film is provided at the liquid-liquid interface; and
(c) removing the first and second liquids to provide an unsupported polyelectrolyte multilayer film.
10. The method according to claim 9 wherein the second liquid is in the form of a droplet.
11. The method according to claim 9 wherein the unsupported polyelectrolyte multilayer film is in the form of a hollow capsule.