Coating method
A method of coating a material onto projections provided on a patch. The method includes applying a coating solution containing the material to at least the projections and drying the coating solution to at least the projections using a gas flow.
1. A microprojection array comprising microprojections coated with a material, wherein the material is coated onto the microprojections by using a gas flow to distribute a coating solution containing the material over the microprojections and using a gas flow to dry the coating solution, and wherein the coating solution has at least one of:
a) a viscosity of between 10 −3 Pa·S and 1 Pa·S; and
b) a surface tension of between 0.023 N/m and 0.073 N/m.
2. A microprojection array according to claim 1 , wherein the material includes at least one of:
a) nanoparticles;
b) a nucleic acid or protein;
c) an antigen, allergen, or adjuvant;
d) parasites, bacteria, viruses, or virus-like particles;
e) quantum dots, SERS tags, Raman tags or other nanobiosensors;
f) metals or metallic compounds; and,
g) molecules, elements or compounds.
3. A microprojection array according to claim 1 , wherein the coating solution further includes a therapeutic agent.
4. A microprojection array according to claim 3 , wherein the therapeutic agent is at least one of:
a) DNA; and,
b) protein.
5. A microprojection array according to claim 1 , wherein the coating solution includes the material and at least one of:
a) a viscosity enhancer;
b) a surfactant; or
c) an adjuvant.
6. A microprojection array according to claim 5 , wherein at least one of:
a) the viscosity enhancer is 0% to 90% of the coating solution; and,
b) the surfactant is 0% to 90% of the coating solution.
7. A microprojection array according to claim 5 , wherein the viscosity enhancer is methylcellulose (MC), carboxymethylcellulose (CMC), gelatin, agar, agarose or any combination thereof.
8. A microprojection array according to claim 1 , wherein the coating solution has a viscosity of 0.01-0.06 Pa·S.
9. A microprojection array according to claim 1 , wherein the coating solution has a surface tension of 0.03-0.04 N/m.
10. A microprojection array according to claim 1 , wherein the microprojections are provided on a patch having a surface area of approximately 0.16 cm 2 .
11. A microprojection array according to claim 1 , wherein the microprojections have a length of between 10 to 400 μm.
12. A microprojection array according to claim 11 , wherein the microprojections have a length of 90 μm.
13. A microprojection array according to claim 1 wherein the microprojections have a radius of curvature of greater than 1 μm.
14. A microprojection array according to claim 13 , wherein the microprojections have a radius of curvature greater than 5 μm.
15. A microprojection array according to claim 1 , wherein the microprojections include a support section and a targeting section.
16. A microprojection array according to claim 1 , wherein the microprojections are solid.
17. A microprojection array according to claim 1 , wherein the microprojections are non-porous and non-hollow.
18. A microprojection array according to claim 1 , wherein the microprojection array is one of:
a) hydrophobic; and,
b) hydrophilic.
19. A microprojection array comprising microprojections coated with a material, wherein the material is coated onto the microprojections by using a gas flow to distribute a coating solution containing the material over the microprojections and using a gas flow to dry the coating solution, wherein the coating solution includes die material and at least one of a viscosity enhancer, a surfactant or an adjuvant, and wherein at least one of:
a) the viscosity enhancer is 0% to 90% of the coating solution; and,
b) the surfactant is 0% to 90% of the coating solution.
20. A microprojection array comprising microprojections coated with a material, wherein the material is coated onto the microprojections by using a gas flow to distribute a coating solution containing the material over the microprojections and using a gas flow to dry the coating solution, wherein the coating solution includes the material and at least one of a viscosity enhancer, a surfactant or an adjuvant, and wherein the viscosity enhancer is methylcellulose (MC), carboxymethylcellulose (CMC), gelatin, agar, agarose or any combination thereof.
21. A microprojection array comprising microprojections coated with a material, wherein the material is coated onto the microprojections by using a gas flow to distribute a coating solution containing the material over the microprojections and using a gas flow to dry the coating solution, and wherein the microprojections are provided on a patch having a surface area of approximately 0.16 cm 2 .
22. A microprojection array comprising microprojections coated with a material, wherein the material is coated onto the microprojections by using a gas flow to distribute a coating solution containing the material over the microprojections and using a gas flow to dry the coating solution, and wherein the microprojections have a radius of curvature of greater than 1 μm.
23. A microprojection array comprising microprojections coated with a material, wherein the material is coated onto the microprojections by using a gas flow to distribute a coating solution containing the material over the microprojections and using a gas flow to dry the coating solution, and wherein the microprojections include a support section and a targeting section.